Collection of clinical data for graphical representation and analysis

ABSTRACT

A method of treating a patient and an external programmer for use with a neurostimulator. Electrical stimulation energy is serially conveyed into tissue of the patient via different combinations of electrodes implanted within the patient, thereby creating one or more clinical effects for each of the different electrode combinations. An influence of each of the different electrode combinations on the clinical effect(s) is determined. A graphical indication of the one or more clinical effects is generated based on the determined electrode combination influences. A graphical representation of the electrodes is displayed. The graphical indication of the clinical effect(s) is displayed adjacent the graphical electrode representation, such that a user can view an extent to which each of the different electrode combinations influences the clinical effect(s).

RELATED APPLICATION DATA

The present application claims the benefit under 35 U.S.C. §119 to U.S.provisional patent application Ser. No. 61/491,092, filed May 27, 2011.The foregoing application is hereby incorporated by reference into thepresent application in its entirety.

FIELD OF THE INVENTION

The present invention relates to tissue stimulation systems, and moreparticularly, to user interfaces and methods for controlling thedistribution of electrical current on neurostimulation leads.

BACKGROUND OF THE INVENTION

Implantable neurostimulation systems have proven therapeutic in a widevariety of diseases and disorders. Pacemakers and Implantable CardiacDefibrillators (ICDs) have proven highly effective in the treatment of anumber of cardiac conditions (e.g., arrhythmias). Spinal CordStimulation (SCS) systems have long been accepted as a therapeuticmodality for the treatment of chronic pain syndromes, and theapplication of tissue stimulation has begun to expand to additionalapplications, such as angina pectoris and incontinence. Further, inrecent investigations, Peripheral Nerve Stimulation (PNS) systems havedemonstrated efficacy in the treatment of chronic pain syndromes andincontinence, and a number of additional applications are currentlyunder investigation.

More pertinent to the present inventions described herein, Deep BrainStimulation (DBS) has been applied therapeutically for well over adecade for the treatment of neurological disorders, includingParkinson's Disease, essential tremor, dystonia, and epilepsy, to namebut a few. Further details discussing the treatment of diseases usingDBS are disclosed in U.S. Pat. Nos. 6,845,267, 6,845,267, and 6,950,707,which are expressly incorporated herein by reference.

Each of these implantable neurostimulation systems typically includesone or more electrode carrying stimulation leads, which are implanted atthe desired stimulation site, and a neurostimulator implanted remotelyfrom the stimulation site, but coupled either directly to theneurostimulation lead(s) or indirectly to the neurostimulation lead(s)via a lead extension. The neurostimulation system may further comprise ahandheld external control device to remotely instruct theneurostimulator to generate electrical stimulation pulses in accordancewith selected stimulation parameters. Typically, the stimulationparameters programmed into the neurostimulator can be adjusted bymanipulating controls on the external control device to modify theelectrical stimulation provided by the neurostimulator system to thepatient.

Thus, in accordance with the stimulation parameters programmed by theexternal control device, electrical pulses can be delivered from theneurostimulator to the stimulation electrode(s) to stimulate or activatea volume of tissue in accordance with a set of stimulation parametersand provide the desired efficacious therapy to the patient. The beststimulus parameter set will typically be one that delivers stimulationenergy to the volume of tissue that must be stimulated (the targettissue region) in order to provide the therapeutic benefit (e.g.,treatment of movement disorders), while minimizing the non-target tissueregion that is stimulated. A typical stimulation parameter set mayinclude the electrodes that are acting as anodes or cathodes, as well asthe amplitude, duration, and rate of the stimulation pulses.

Significantly, non-optimal electrode placement and stimulation parameterselections may result in excessive energy consumption due to stimulationthat is set at too high an amplitude, too wide a pulse duration, or toofast a frequency; inadequate or marginalized treatment due tostimulation that is set at too low an amplitude, too narrow a pulseduration, or too slow a frequency; or stimulation of neighboring cellpopulations that may result in undesirable side-effects.

For example, bilateral DBS of the subthalamic nucleus has been proven toprovide effective therapy for improving the major motor signs ofadvanced Parkinson's disease, and although the bilateral stimulation ofthe subthalamic nucleus is considered safe, an emerging concern is thepotential negative consequences that it may have on cognitivefunctioning and overall quality of life (see A. M. M. Frankemolle, etal., Reversing Cognitive-Motor Impairments in Parkinson's DiseasePatients Using a Computational Modelling Approach to Deep BrainStimulation Programming, Brain 2010; pp. 1-16). In large part, thisphenomenon is due to the small size of the subthalamic nucleus, whichmay range from the size of a pea to the size of a peanut, with varyingshapes from spherical to kidney-shape. Even with the electrodes arelocated predominately within the sensorimotor territory, the electricfield generated by DBS is non-discriminately applied to all neuralelements surrounding the electrodes, thereby resulting in the spread ofcurrent to neural elements affecting cognition. As a result, diminishedcognitive function during stimulation of the subthalamic nucleus mayoccur do to non-selective activation of non-motor pathways within oraround the subthalamic nucleus.

Thus, it is crucial that proper location and maintenance of the leadposition be accomplished in order to continuously achieve efficacioustherapy. Lead displacements of less than a millimeter may have adeleterious effect on the patient's therapy. Because the stimulationregion needs to be in the correct location to achieve optimal therapyand minimization of side-effects, stimulation leads typically carry manyelectrodes (e.g., four), so that at least one of the electrodes is nearthe target and allow programming of the electrodes to place thestimulation field in that region of interest.

The large number of electrodes available, combined with the ability togenerate a variety of complex stimulation pulses, presents a hugeselection of stimulation parameter sets to the clinician or patient. Inthe context of DBS, neurostimulation leads with a complex arrangement ofelectrodes that not only are distributed axially along the leads, butare also distributed circumferentially around the neurostimulation leadsas segmented electrodes, can be used.

To facilitate such selection, the clinician generally programs theexternal control device, and if applicable the neurostimulator, througha computerized programming system. This programming system can be aself-contained hardware/software system, or can be defined predominantlyby software running on a standard personal computer (PC). The PC orcustom hardware may actively control the characteristics of theelectrical stimulation generated by the neurostimulator to allow theoptimum stimulation parameters to be determined based on patientfeedback and to subsequently program the external control device withthe optimum stimulation parameters.

When electrical leads are implanted within the patient, the computerizedprogramming system may be used to instruct the neurostimulator to applyelectrical stimulation to test placement of the leads and/or electrodes,thereby assuring that the leads and/or electrodes are implanted ineffective locations within the patient. Once the leads are correctlypositioned, a fitting procedure, which may be referred to as anavigation session, may be performed using the computerized programmingsystem to program the external control device, and if applicable theneurostimulator, with a set of stimulation parameters that bestaddresses the neurological disorder(s).

As physicians and clinicians become more comfortable with implantingneurostimulation systems and time in the operating room decreases,post-implant programming sessions are becoming a larger portion ofprocess. Furthermore, because the body tends to adapt to the specificstimulation parameters currently programmed into a neurostimulationsystem, or the full effects of stimulation are not manifest in a shortperiod of time (i.e., not observed within a programming session),follow-up programming procedures are often needed.

For example, in the context of DBS, the brain is dynamic (e.g., due todisease progression, motor re-learning, or other changes), and a program(i.e., a set of stimulation parameters) that is useful for a period oftime may not maintain its effectiveness and/or the expectations of thepatient may increase. Further, physicians typically treat the patientwith stimulation and medication, and proper amounts of each are requiredfor optimal therapy. Thus, after the DBS system has been implanted andfitted, the patient may have to schedule another visit to the physicianin order to adjust the stimulation parameters of the DBS system if thetreatment provided by the implanted DBS system is no longer effective orotherwise is not therapeutically or operationally optimum due to, e.g.,disease progression, motor re-learning, or other changes.

Regardless of the skill of the physician or clinician, neurostimulationprogramming sessions can be especially lengthy when programmingcomplicated neurostimulation systems, such as DBS systems, wherepatients usually cannot feel the effects of stimulation, and the effectsof the stimulation may be difficult to observe, are typicallysubjective, or otherwise may take a long time to become apparent.Clinical estimates suggest that 18-36 hours per patient are necessary toprogram and assess DBS patients with current techniques (see Hunka K.,et al., Nursing Time to Program and Assess Deep Brain Stimulators inMovement Disorder Patients, J. Neursci Nurs. 37: 204-10), which is anextremely large time commitment for both the physician/clinician and thepatient.

Significantly contributing to the lengthy process of programmingneurostimulation system is the fact the location of the electrodesrelative to the target tissue region is not exactly known when theneurostimulation lead or leads are initially implanted within the brainof the patient. In a typical programming session, the boundaries of atargeted region or structure relative to the electrodes can bedetermined by observing and recording a substantial amount of clinicalinformation observed during the programming session of each patient isrecorded. Typically this is accomplished by incrementally increasing theamplitude of electrical stimulation energy on each individual electrodeone at a time, for each amplitude increment, observing and manuallyrecording on a relatively large paper spread sheet, clinicalinformation, such as the types of therapeutic effects and side-effects,the threshold values of these therapeutic effects and side-effects, theextent of these therapeutic effects and side-effects. Based on thisobserved information, the physician or clinician may determine theelectrodes having the greatest influence on the surrounding tissue,whether such influence causes a therapeutic effect or a side-effect, theneurostimulation system can be programmed with the best stimulationparameter sets (i.e., those that maximize the volume of target tissue,while minimizing the volume of non-target tissue).

Notably, as the stimulation level of the electrodes that within thetargeted region is incrementally increased, first a therapeutic level isreached, and then unwanted side-effects are reached. The boundaries ofthe target tissue region are determined to be around the therapeuticlevel, but below the side-effects level. The electrodes located outsideof the target tissue region (in theory) have not therapeutic level, onlya side-effect level. Once the boundaries the target tissue region aredetermined, the neurostimulation system can be programmed, such that theresulting electrical stimulation field covers the target tissue region(i.e., the shape and size of the electrical stimulation matches theshape and size of the target tissue region).

While the manual recording of this clinical information has some utilityin facilitating programming sessions, the recorded clinical informationis not represented to the physician or clinician in a manner that thephysician or clinician can readily taken advantage of in the currentprogramming session, and certainly during subsequent programmingsessions where the same physician or clinician will not have access tothis recorded clinical information.

To facilitate determination of the location of the electrodes relativeto the target tissue region or regions, and even the non-target tissueregion or regions, a computerized programming system may optionally becapable of storing one or more anatomical regions of interest, which maybe registered within the neurostimulation leads when implanted with thepatient.

The anatomical region of interest may be a target tissue region, thestimulation of which is known or believed to provide the needed therapyto the patient. For example, if the DBS indication is Parkinson'sdisease, the target tissue region may be the subthalamic nucleus (STN)or the globus pallidus (GPi). If the DBS indication is Essential Tremor,the target tissue region may be the thalamus. If the DBS indication isdepression, the target tissue region may be one or more of the nucleusacumbens, ventral striatum, ventral capsule, anterior capsule, or theBrodmann's area 25. If the DBS indication is epilepsy, the target tissueregion may be preferably the anterior nucleus. If the DBS indication isa gait disorder, the target tissue region may be the pedunculopontinenucleus (PPN). If the DBS indication is dementia, Alzheimer's disease ormemory disorders, the target tissue region may be anywhere in the Papezcircuit.

The anatomical region of interest may be a non-target tissue region, thestimulation of which is known or believed to provide an undesirableside-effect for the patient. For example, stimulation of medial to theSTN may cause eye deviations, and stimulation of the substantia nigramay cause symptoms of depression.

Notably, the anatomical region of interest may not be strictlyanatomical, but rather may simply represent some arbitrary volume oftissue that, when stimulated, provides therapy or creates a side-effect.The anatomical region of interest may be naturally defined (e.g., ananatomical structure corresponding to the target tissue volume maynaturally provide the boundaries that delineate it from the surroundingtissue) or may be defined by a graphical marking). The anatomical regionof interest may be obtained from a generally available atlas, and in thecase of DBS, a brain atlas, which may be derived from the generalpopulation or a previous patient, or may be obtained from a patientspecific atlas derived from, e.g., a magnetic resonant imager (MRI),computed tomography (CT), X-ray, fluoroscopy, ventriculography,ultrasound, or any other imaging modality or a merging of any or all ofthese modalities.

Although the use of a generalized atlas may be quite helpful whenoptimizing the stimulation parameters that are ultimately programmedinto the neurostimulation system, these types of atlases are not patientspecific, and thus, cannot account for patient specific physiology. Evenif a patient-specific atlas is used, any errors in registration with theneurostimulation leads may prevent optimized programming of theneurostimulation system.

There, thus, remains a need for a user interface that more efficientlyallows the programming of neurostimulation systems.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the present inventions, a method oftreating a patient is provided. The method comprises serially conveyingelectrical stimulation energy into tissue (e.g., brain tissue) of thepatient via different combinations of electrodes implanted within thepatient, thereby creating one or more clinical effects (e.g., atherapeutic effect and/or a side-effect) for each of the differentelectrode combinations. In one embodiment, each electrode combinationhas only one electrode. In another embodiment, at least one of theelectrode combinations comprises a fractionalized electrode combination.

The method further comprises determining an influence of each of thedifferent electrode combinations on the clinical effect(s), andgenerating a graphical indication of the clinical effect(s) based on thedetermined electrode combination influences. The method furthercomprises displaying a graphical representation of the electrodes, anddisplaying the graphical indication of the clinical effect(s) adjacentthe graphical electrode representation, such that a user can determinean extent to which each of the different electrode combinationsinfluences the clinical effect(s). The electrical stimulation energy maybe conveyed from a neurostimulator, in which case, the method mayfurther comprise programming the neurostimulator based on the determinedextent to which the each different electrode combination influences theclinical effects(s). The method may further comprise recording data incomputer memory indicating the determined influence of the eachdifferent electrode combination on the clinical effect(s).

One method further comprises incrementally increasing an intensity levelof the conveyed electrical stimulation energy for each of the differentelectrode combinations, wherein the influence of the each differentelectrode combination on the clinical effect(s) is determined for eachof the incremental intensity levels. In this case, the clinicaleffect(s) may include one or more therapeutic effects, and the influenceof the each different electrode combination on the therapeutic effect(s)may be determined by determining the range of incremental intensitylevels at which a metric of the therapeutic effect(s) (e.g., aperception threshold of the therapeutic effect(s)) occurs.

In this method, the clinical effect(s) may further comprise one or moreside-effects, and the influence of the each different electrodecombination on the side-effect(s) may be determined by determining theincremental intensity level at which a metric of the side-effect(s)(e.g., a perception threshold of the side-effect(s), an uncomfortablethreshold of the side-effect(s), or an intolerable threshold of theside-effect(s)) initially occurs. In this case, the influence of theeach different electrode combination on the therapeutic effect(s) mayfurther be determined by determining the highest intensity level atwhich the therapeutic effect metric(s) occur prior to the initialoccurrence of the side-effect metric(s). The graphical indication of theclinical effect(s) may comprise a bar map having a plurality of bars,each of which indicates for the each different electrode combination thehighest intensity level at which the therapeutic effect metric(s) occurprior to the initial occurrence of the side-effect metric(s).

In this method, the therapeutic effect metric may alternatively be arelative level of the therapeutic effect(s), in which case, thegraphical indication of the clinical effect(s) may comprise a bar mapfor each of the electrode combinations, each bar map having a barindicating the relative level of the therapeutic effect(s) at the eachincremental intensity level. The therapeutic effect(s) may comprise aplurality of therapeutic effects, and the relative level may be acomposite score as a function of individual scores of the therapeuticeffects.

In this method, the influence of the each different electrodecombination on the clinical effect(s) may alternatively be determined bydetermining the electrode combinations that most influence thetherapeutic effect(s), and wherein the graphical indication of theclinical effect(s) comprises at least one target tissue region displayedadjacent the electrode combinations in the graphical electroderepresentation determined to most influence the therapeutic effect(s).In this case, the influence of the each different electrode combinationon the clinical effect(s) may be determined by determining the electrodecombinations that most influence the side-effect, and the graphicalindication of the clinical effect(s) may comprise at least onenon-target tissue region displayed adjacent the electrode combinationsin the graphical electrode representation determined to most influencethe side-effect. Optionally, this method may further comprise estimatingone of an electric field or a region of tissue activation at the highestincremental intensity level at which the therapeutic effect(s) occursfor the each different electrode combination, in which case, the targettissue region may be based on the estimated electric field or region oftissue activation.

In accordance with a second aspect of the present inventions, anexternal programmer for use with a neurostimulator is provided. Theneurostimulator comprises output circuitry configured for communicatingwith the neurostimulator, and control circuitry configured forinstructing the neurostimulator via the output circuitry to seriallyconvey electrical stimulation energy into tissue of a patient viadifferent combinations of electrodes implanted within the patient,thereby creating one or more clinical effects (e.g., a therapeuticeffect and/or a side-effect) for each of the different electrodecombinations. In one embodiment, each electrode combination has only oneelectrode. In another embodiment, at least one of the electrodecombinations comprises a fractionalized electrode combination.

The neurostimulator further comprises processing circuitry configuredfor determining an influence of each of the different electrodecombinations on the clinical effect(s), and generating a graphicalindication of the clinical effect(s) based on the determined electrodecombination influences. The control circuitry is further configured forinstructing a display device to display the graphical indication of theclinical effect(s) adjacent a graphical representation of theelectrodes, such that the user can determine an extent to which each ofthe different electrode combinations influences the clinical effect(s).The control circuitry may further be configured for programming theneurostimulator via the output circuitry based on the determined extentto which the each different electrode combination influences theclinical effect(s).

The external programmer may further comprise a user interface configuredfor allowing a user to enter clinical information on the clinicaleffect(s) for each different electrode combination, in which case, theprocessing circuitry may be configured for determining the influence ofthe each different electrode combination on the clinical effect(s) basedon the clinical information entered by the user. The processingcircuitry may determine the influence of each of the different electrodecombinations on the clinical effect(s) by, e.g., deriving such influencefrom the clinical information entered by the user, or if the clinicalinformation entered by the user is, itself, an influence of each of thedifferent electrode combinations on the clinical effect(s), by merelyaccepting the clinical information as such influence. The externalprogrammer may further comprise monitoring circuitry configured formonitoring the clinical effect(s) for each different electrodecombination, in which case, the processing circuitry may be configuredfor determining the influence of the each different electrodecombination on the clinical effect(s) based on the monitored clinicaleffect(s). The external programmer may further comprise memoryconfigured for storing data indicating the determined influence of theeach different electrode combination on the clinical effect(s).

In one embodiment, control circuitry is further configured forinstructing the neurostimulator via the output circuitry toincrementally increase an intensity level of the conveyed electricalstimulation energy for each of the different electrode combinations, andthe processing circuitry is configured for determining the influence ofthe each different electrode combination on the clinical effect(s) foreach of the incremental intensity levels. In this case, the clinicaleffect(s) may comprise one or more therapeutic effects, and theprocessing circuitry may be configured for determining the influence ofthe each different electrode combination on the therapeutic effect(s) bydetermining the range of incremental intensity levels at which a metricof the therapeutic effect(s) (e.g., a perception threshold of thetherapeutic effect(s)) occurs.

In this embodiment, the clinical effect(s) may further comprises one ormore side-effects, in which case, the processing circuitry may befurther configured for determining the influence of the each differentelectrode combination on the side-effect(s) by determining theincremental intensity level at which a metric of the side-effect(s)(e.g., a perception threshold of the one or more side-effects, anuncomfortable threshold of the one or more side-effects, or anintolerable threshold of the one or more side-effects) initially occurs.The processing circuitry may be further configured for determining theinfluence of the each different electrode combination on the therapeuticeffect(s) by determining the highest intensity level at which thetherapeutic effect metric(s) occur prior to the initial occurrence ofthe side-effect metric(s). The graphical indication of the clinicaleffect(s) may comprise a bar map having a plurality of bars, each ofwhich indicates for the each different electrode combination the highestintensity level at which the therapeutic effect metric(s) occur prior tothe initial occurrence of the side-effect metric(s).

In this embodiment, the therapeutic effect metric may alternatively be arelative level of the one or more therapeutic effects, in which case,the graphical indication of the clinical effect(s) may comprises a barmap for each of the electrode combinations, each bar map having a barindicating the relative level of the therapeutic effect(s) at eachincremental intensity level. The therapeutic effect(s) may comprises aplurality of therapeutic effects, and the relative level ma be compositescore as a function of individual scores of the therapeutic effects.

In this embodiment, the processing circuitry may alternatively beconfigured for determining the influence of the each different electrodecombination on the clinical effect(s) by determining the electrodecombinations that most influence the therapeutic effect(s), and thegraphical indication of the clinical effect(s) may comprise at least onetarget tissue region displayed adjacent the electrode combinations inthe graphical electrode representation determined to most influence thetherapeutic effect(s). The processing circuitry may further beconfigured for determining the influence of the each different electrodecombination on the clinical effect(s) by determining the electrodecombinations that most influence the side-effect, in which case, thegraphical indication of the clinical effect(s) may comprise at least onenon-target tissue region displayed adjacent the electrode combinationsin the graphical electrode representation determined to most influencethe side-effect. The processing circuitry may further be configured forestimating one of an electric field or a region of tissue activation atthe highest incremental intensity level at which the therapeuticeffect(s) occurs for the each different electrode combination, whereinthe target tissue region is based on the estimated electric field orregion of tissue activation.

In accordance with a third aspect of the present inventions, a method oftreating a patient is provided. The method comprises conveyingelectrical stimulation energy into tissue (e.g., brain tissue) of thepatient via a specified combination of a plurality of electrodes,thereby creating one or more clinical effects, and determining aninfluence of the specified electrode combination on the clinicaleffect(s). The method further comprises displaying an anatomical regionof interest in registration with a graphical representation of theplurality of electrodes. The anatomical region of interest may be, e.g.,an anatomical structure functionally delineated from surrounding tissueor an arbitrarily defined anatomical region of interest. The anatomicalregion of interest may be a therapy tissue region or a side-effecttissue region.

The method further comprises modifying the displayed anatomical regionof interest based on the determined influence of the specified electrodecombination on the clinical effect(s). The displayed anatomical regionof interest may be modified by, e.g., spatially translating thedisplayed anatomical region of interest relative to the graphicalelectrode representation or changing the shape of the displayedanatomical region of interest. The electrical stimulation energy may beconveyed from a neurostimulator, in which case, the method may furthercomprise programming the neurostimulator based on the modifiedanatomical region of interest. The method may further comprise recordingthe modified anatomical region of interest in computer memory.

One method further comprises determining a displayed proximity betweenthe displayed anatomical region of interest and the specified electrodecombination in the graphical electrode representation, and implying anactual proximity between the anatomical region of interest and thespecified electrode combination based on the determined influence of thespecified electrode combination on the clinical effect(s). In this case,the displayed anatomical region of interest may be modified by spatiallytranslating the displayed anatomical region of interest relative to thespecified electrode combination in the graphical electroderepresentation to better match the displayed proximity to the actualproximity. If the displayed proximity is greater than the actualproximity, the displayed anatomical region of interest may be spatiallytranslated closer to the specified electrode combination in thegraphical electrode representation. If the displayed proximity is lessthan the actual proximity, the displayed anatomical region of interestmay be spatially translated further from the specified electrodecombination in the graphical electrode representation.

Another method further comprises displaying another anatomical region ofinterest in registration with a graphical representation of theplurality of electrodes, in which case, the clinical effect(s) comprisea therapeutic effect and a side-effect, the anatomical region ofinterest is a therapy tissue region, and the other anatomical region ofinterest is a side-effect tissue region. The influence of the specifiedelectrode combination on the clinical effect(s) can be determined bydetermining a relative influence of the specified electrode combinationon the therapeutic effect and the side-effect, and the displayed therapytissue region and displayed side-effect tissue region may be modified byspatially translating the displayed therapy tissue region and theside-effect tissue region relative to the specified electrodecombination in the graphical electrode representation based on thedetermined relative influence of the specified electrode combination onthe therapeutic effect and the side-effect.

For example, if the specified electrode combination in the graphicalelectrode representation is closer to the displayed therapy tissueregion than the displayed side-effect tissue region, the displayedtherapy tissue region may be spatially translated further from thespecified electrode combination in the graphical electroderepresentation and the displayed side-effect tissue region may bespatially translated closer to the specified electrode combination inthe graphical electrode representation if the specified electrodecombination is determined to influence the side-effect more than thetherapeutic effect.

As another example, if the specified electrode combination in thegraphical electrode representation is closer to the displayedside-effect tissue region than the displayed therapy tissue region, thedisplayed therapy tissue region may be spatially translated closer tothe specified electrode combination in the graphical electroderepresentation and the displayed side-effect tissue region is spatiallytranslated further from the specified electrode combination in thegraphical electrode representation if the specified electrodecombination is determined to influence the therapeutic effect more thanthe side-effect.

Still another method further comprises serially conveying electricalstimulation energy into the tissue of the patient via first and secondcombinations of the electrodes, thereby creating the clinical effect(s),with the first electrode combination in the graphical electroderepresentation being further away from the displayed anatomical regionof interest than the second electrode combination in the graphicalelectrode representation. The method further comprises determining aninfluence of each of the first and second electrode combinations on theclinical effect(s), wherein the first electrode combination isdetermined to have a higher influence on the clinical effect(s) than thesecond electrode combination. The displayed anatomical region ofinterest may then be modified by spatially translating the displayedanatomical region of interest away from the second electrode combinationin the graphical electrode representation towards the first electrodecombination in the graphical electrode representation.

Yet another method further comprises serially conveying electricalstimulation energy into tissue of the patient via different combinationsof electrodes implanted within the patient, thereby creating one or moreclinical effects for each of the different electrode combinations. Theclinical effect(s) comprises one or more therapeutic effects and one ormore side-effects, and the displayed anatomical region is a therapytissue region. The method further comprises incrementally increasing anintensity level of the conveyed electrical stimulation energy for eachof the different electrode combinations, determining the influence ofeach different electrode combination on the clinical effect(s) bydetermining the highest intensity level at which a metric of thetherapeutic effect(s) occurs prior to an initial occurrence of a metricof the side-effect(s). The displayed therapy tissue region may bemodified by changing the shape of the therapy tissue region based on thedetermined highest intensity levels for the specified electrodecombinations.

In accordance with a fourth aspect of the present inventions, anexternal programmer for use with a neurostimulator is provided. Theexternal programmer comprises output circuitry configured forcommunicating with the neurostimulator, and control circuitry configuredfor instructing the neurostimulator via the output circuitry to conveyelectrical stimulation energy into the tissue of the patient via aspecified combination of a plurality of electrodes, thereby creating oneor more clinical effects, and for instructing a display device todisplay an anatomical region of interest in registration with agraphical representation of a plurality of electrodes. The anatomicalregion of interest may be, e.g., an anatomical structure functionallydelineated from surrounding tissue or an arbitrarily defined anatomicalregion of interest. The anatomical region of interest may be a therapytissue region or a side-effect tissue region.

The external programmer further comprises processing circuitryconfigured for determining an influence of the specified electrodecombination on the clinical effect(s). The processing circuitry maydetermine the influence of each of the different electrode combinationson the clinical effect(s) by, e.g., deriving such influence fromclinical information entered by the user, or if the clinical informationentered by the user is, itself, an influence of each of the differentelectrode combinations on the clinical effect(s), by merely acceptingthe clinical information as such influence. The processing circuitry isfurther configured for modifying the anatomical region of interest basedon the determined influence of the specified electrode combination onthe clinical effect(s). The displayed anatomical region of interest maybe modified by, e.g., spatially translating the displayed anatomicalregion of interest relative to the graphical electrode representation orchanging the shape of the displayed anatomical region of interest. Thecontrol circuitry may be further configured for programming theneurostimulator via the output circuitry based on the modifiedanatomical region of interest. The external programmer may furthercomprise memory configured for storing the modified anatomical region ofinterest.

In one embodiment, the processing circuitry is further configured fordetermining a displayed proximity between the displayed anatomicalregion of interest and the specified electrode combination in thegraphical electrode representation, implying an actual proximity betweenthe anatomical region of interest and the specified electrodecombination based on the determined influence of the specified electrodecombination on the clinical effect(s), and modifying the displayedanatomical region of interest by spatially translating the displayedanatomical region of interest relative to the specified electrodecombination in the graphical electrode representation to better matchthe displayed proximity to the actual proximity. The processingcircuitry may be configured for spatially translating the displayedanatomical region of interest closer to the specified electrodecombination in the graphical electrode representation if the displayedproximity is greater than the actual proximity. The processing circuitrymay be configured for spatially translating the displayed anatomicalregion of interest further from the specified electrode combination inthe graphical electrode representation if the displayed proximity isless than the actual proximity.

In another embodiment, the control circuitry is further configured forinstructing the display device to display another anatomical region ofinterest in registration with a graphical representation of a pluralityof electrodes. In this case, the clinical effect(s) may comprise atherapeutic effect and a side-effect, the anatomical region of interestmay be a therapy tissue region, the other anatomical region of interestmay be a side-effect tissue region. The processing circuitry isconfigured for determining the influence electrode combination on theclinical effect(s) by determining a relative influence of the specifiedelectrode combination on the therapeutic effect and the side-effect, andmodifying the displayed therapy tissue region and displayed side-effecttissue region by spatially translating the displayed therapy tissueregion and the side-effect tissue region relative to the specifiedelectrode combination in the graphical electrode representation based onthe determined relative influence of the specified electrode combinationon the therapeutic effect and the side-effect.

In one example, if the specified electrode combination in the graphicalelectrode representation is closer to the displayed therapy tissueregion than the displayed side-effect tissue region, the processingcircuitry may be configured for spatially translating the displayedtherapy tissue region further from the specified electrode combinationin the graphical electrode representation and the displayed side-effecttissue region closer to the specified electrode combination in thegraphical electrode representation if the specified electrodecombination is determined to influence the side-effect more than thetherapeutic effect.

In another example, if the specified electrode combination in thegraphical electrode representation is closer to the displayedside-effect tissue region than the displayed therapy tissue region, theprocessing circuitry may be configured for spatially translating thedisplayed therapy tissue region closer to the specified electrodecombination in the graphical electrode representation and the displayedside-effect tissue region further from the specified electrodecombination in the graphical electrode representation if the specifiedelectrode combination is determined to influence the therapeutic effectmore than the side-effect.

In still another embodiment, the control circuitry is configured forserially conveying electrical stimulation energy into the tissue of thepatient via first and second combinations of the electrodes, therebycreating the clinical effect(s), with the first electrode combination inthe graphical electrode representation being further away from thedisplayed anatomical region of interest than the second electrodecombination in the graphical electrode representation. The processingcircuitry is configured for determining an influence of each of thefirst and second electrode combinations on the clinical effect(s). Ifthe first electrode combinations is determined to have a higherinfluence on the clinical effect(s) than the second electrodecombination, the processing circuitry may be further configured formodifying the displayed anatomical region of interest by spatiallytranslating the displayed anatomical region of interest away from thesecond electrode combination in the graphical electrode representationtowards the first electrode combination in the graphical electroderepresentation.

In yet another embodiment, the control circuitry is configured forserially conveying electrical stimulation energy into tissue of thepatient via different combinations of electrodes implanted within thepatient, thereby creating one or more clinical effects for each of thedifferent electrode combinations. In this case, the clinical effect(s)comprises one or more therapeutic effects and one or more side-effects,and the displayed anatomical region is a therapy tissue region. Thecontrol circuitry is further configured for incrementally increasing anintensity level of the conveyed electrical stimulation energy for eachof the different electrode combinations. The processing circuitry isconfigured for determining the influence of the each different electrodecombination on the one or more clinical effects by determining thehighest intensity level at which a metric of the therapeutic effect(s)occurs prior to an initial occurrence of a metric of the side-effect(s),and modifying the displayed therapy tissue region by changing the shapeof the therapy tissue region based on the determined highest intensitylevels for respective the specified electrode combinations.

In accordance with a fifth aspect of the present inventions, a method oftreating a patient using a plurality of electrodes implanted withintissue (e.g., brain tissue) of the patient is provided. The methodcomprises selecting one of a plurality of different pre-defined shapes(e.g., a circular shape and a pear-shape) for an electric field, anddefining a location of the electric field relative to a graphicalrepresentation of the electrodes. The method further comprisesdetermining a combination of the electrodes (which may befractionalized) based on the one selected shape and defined location ofthe electric field, and conveying electrical stimulation energy into thetissue of the patient via the determined electrode combination. In onemethod, the electrical stimulation energy is conveyed from aneurostimulator, in which case, the method may further compriseprogramming the neurostimulator to convey the electrical stimulationenergy via the automatically determined electrode combination.

An optional method further comprises selecting another one of theplurality of different pre-defined shapes for another electric field,and defining a location of the other electric field relative to thegraphical representation of the electrodes. In this case, thecombination of the electrodes are determined based on both the oneselected shape and defined location of the electric field and the otherselected shape and defined location of the other electric field. Anotheroptional method further comprises adjusting an intensity level of theconveyed electrical stimulation energy, wherein a size of the displayedelectric field is adjusted in accordance with the adjusted intensitylevel.

A representation of the electric field may be displayed relative to thegraphical electrode representation. In this case, the method may furthercomprise displaying a therapy tissue region, and comparing the displayedtherapy tissue region to the plurality of different pre-defined electricfield shapes, wherein the one pre-defined shape is selected based on thecomparison. For example, the pre-defined shape that best matches thedisplayed therapy tissue region may be selected as the one pre-definedshape. In another method, the therapy tissue region is displayedrelative to the graphical electrode representation, and the definedlocation of the electric field is defined to match the location of thedisplayed therapy tissue region relative to the graphical electroderepresentation.

In one method, the specified electrode combination is automaticallydetermined based on the selected pre-defined shape and the definedlocation of the electric field. In this case, the method may furthercomprise automatically determining a plurality of different combinationsof the electrodes based on the selected pre-defined shape and thedefined location of the electric field, and serially conveyingelectrical stimulation energy into the tissue of the patient via theplurality of determined electrode combinations, thereby creating aclinical effect for each of the determined electrode combinations. Themethod may further comprise assigning a score to each of the determinedelectrode combinations based on the respective clinical effect, andselecting one of the determined electrode combinations based on theassigned scores.

In accordance with a sixth aspect of the present inventions, an externalprogrammer for use with a neurostimulator is provided. The externalprogrammer comprises memory storing a plurality of different pre-definedshapes (e.g., a circular shape and a pear-shape) for an electric field,and a user interface configured for allowing a user to select one of thepre-defined shapes, and for allowing the user to define a location ofthe electric field relative to a graphical representation of theelectrodes. The external programmer further comprises output circuitryconfigured for communicating with the neurostimulator, processingcircuitry configured for determining a combination of the electrodes(which may be fractionalized) based on the one selected shape anddefined location of the electric field, and control circuitry configuredfor instructing the neurostimulator via the output circuitry to conveyelectrical stimulation energy into the tissue of the patient via thedetermined electrode combination. The control circuitry may be furtherconfigured for programming the neurostimulator with the determinedelectrode combination.

In one optional embodiment, the user interface is further configured forallowing a user to select another one of the plurality of differentpre-defined shapes for another electric field, and allowing the user todefine a location of the other electric field relative to the graphicalrepresentation of the electrodes. In this case, the processing circuitrymay be configured for determining the combination of the electrodesbased on both the one selected shape and defined location of theelectric field and the other selected shape and defined location of theother electric field. In another optional embodiment, the controlcircuitry is further configured for adjusting an intensity level of theconveyed electrical stimulation energy, wherein a size of the displayedelectric field is adjusted in accordance with the adjusted intensitylevel.

The control circuitry may further be configured for instructing adisplay device to display a representation of the electric fieldrelative to the graphical electrode representation. In this case, thecontrol circuitry may be configured for displaying a therapy tissueregion to a user, and the user interface may be configured for allowinga user to compare the displayed therapy tissue region to the pluralityof different pre-defined electric field shapes, such that the user mayselect the one pre-defined shape based on the comparison. In anotherembodiment, the control circuitry may be configured for displaying thetherapy tissue region is displayed relative to the graphical electroderepresentation, and the user interface may be configured for allowingthe user to define the location of the electric field to match thelocation of the displayed therapy tissue region relative to thegraphical electrode representation.

In one embodiment, the processing circuitry is configured forautomatically determining the electrode combination based on theselected pre-defined shape and the defined location of the electricfield. In this case, the processing circuitry may be configured forautomatically determining a plurality of different combinations of theelectrodes based on the selected pre-defined shape and the definedlocation of the electric field, and the control circuitry may beconfigured for serially conveying electrical stimulation energy into thetissue of the patient via the plurality of determined electrodecombinations, thereby creating a clinical effect for each of thedetermined electrode combinations. The processing circuitry may beconfigured for assigning a score to each of the determined electrodecombinations based on the respective clinical effect, and the userinterface may be configured for allowing the user to select one of thedetermined electrode combination based on the assigned scores.

Other and further aspects and features of the invention will be evidentfrom reading the following detailed description of the preferredembodiments, which are intended to illustrate, not limit, the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the design and utility of preferred embodimentsof the present invention, in which similar elements are referred to bycommon reference numerals. In order to better appreciate how theabove-recited and other advantages and objects of the present inventionsare obtained, a more particular description of the present inventionsbriefly described above will be rendered by reference to specificembodiments thereof, which are illustrated in the accompanying drawings.Understanding that these drawings depict only typical embodiments of theinvention and are not therefore to be considered limiting of its scope,the invention will be described and explained with additionalspecificity and detail through the use of the accompanying drawings inwhich:

FIG. 1 is a plan view of a Deep Brain Stimulation (DBS) systemconstructed in accordance with one embodiment of the present inventions;

FIG. 2 is a profile view of an implantable pulse generator (IPG) and afirst embodiment of neurostimulation leads used in the DBS system ofFIG. 1;

FIG. 3 is a profile view of an implantable pulse generator (IPG) and asecond embodiment of neurostimulation leads used in the DBS system ofFIG. 1;

FIG. 4 is a cross-sectional view of one of the neurostimulation leads ofFIG. 3, taken along the line 4-4;

FIG. 5 is a cross-sectional view of a patient's head showing theimplantation of stimulation leads and an IPG of the DBS system of FIG.1;

FIG. 6 is front view of a remote control (RC) used in the DBS system ofFIG. 1;

FIG. 7 is a block diagram of the internal components of the RC of FIG.6;

FIG. 8 is a block diagram of the internal components of a clinician'sprogrammer (CP) used in the DBS system of FIG. 1;

FIG. 9 is a plan view of a one embodiment of a programming screen thatcan be generated by the CP of FIG. 8;

FIG. 10 is a plan view of one embodiment of a therapy selection screenthat can be generated by the CP of FIG. 8;

FIG. 11 is a plan view of a neurostimulation lead implanted in tissuewith therapy tissue regions and side-effect tissue regions;

FIG. 12 is a plan view of one embodiment of a clinical effects analysisscreen that can be generated by the CP of FIG. 8;

FIG. 13 is a plan view of a method used by the CP of FIG. 8 to determineone-half of a target tissue region from a bar map generated in theclinical effects analysis screen of FIG. 12;

FIG. 14 is a plan view of a method used by the CP of FIG. 8 to generatethe entire target tissue region from the one-half target tissue regiongenerated in FIG. 13;

FIGS. 15a-15d are plan views of another embodiment of a clinical effectsanalysis screen that can be generated by the CP of FIG. 8;

FIG. 16 is a plan view of still another embodiment of a clinical effectsanalysis screen that can be generated by the CP of FIG. 8;

FIG. 17 is a plan view of a method used by the CP of FIG. 8 to determineone-half of a target tissue region from a bar map generated in theclinical effects analysis screen of FIG. 16;

FIG. 18 is a plan view of a method used by the CP of FIG. 8 to generatethe entire target tissue region from the one-half target tissue regiongenerated in FIG. 17;

FIG. 19 is a plan view of yet another embodiment of a clinical effectsanalysis screen that can be generated by the CP of FIG. 8;

FIGS. 20a-20d are plan views illustrating a series of steps ingenerating a volume map in the clinical effects analysis screen of FIG.19;

FIG. 21 is a plan view of one embodiment of an atlas modification screenthat can be generated by the CP of FIG. 8;

FIGS. 22a-22b are plan views showing an exemplary method used by the CPto modify an atlas via the atlas modification screen of FIG. 21;

FIGS. 23a-23b are plan views showing another exemplary method used bythe CP to modify an atlas via the atlas modification screen of FIG. 21;

FIG. 24 is a plan view showing still another exemplary method used bythe CP to modify an atlas via the atlas modification screen of FIG. 21;

FIG. 25 is a plan view of one embodiment of an electric field selectionscreen that can be generated by the CP of FIG. 8;

FIG. 26 is a plan view of the electric field selection screen of FIG.25, particularly illustrating the user selection of two shapes for anelectric field;

FIG. 27 is a plan view of the electric field selection screen of FIG.25, particularly showing the movement of a selected electric field shapealong a graphical representation of the neurostimulation lead;

FIG. 28 is a plan view of the electric field selection screen of FIG.25, particularly illustrating the modification of a user-selectedelectric field shape;

FIG. 29 is a plan view of a program selection screen that can begenerated by the CP of FIG. 8;

FIG. 30 is a block diagram of an optimization algorithm that can be usedby the CP of FIG. 8 to suggest an optimal electrode configuration forobtaining clinical effects data.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The description that follows relates to a deep brain stimulation (DBS)system. However, it is to be understood that the while the inventionlends itself well to applications in DBS, the invention, in its broadestaspects, may not be so limited. Rather, the invention may be used withany type of implantable electrical circuitry used to stimulate tissue.For example, the present invention may be used as part of a pacemaker, adefibrillator, a cochlear stimulator, a retinal stimulator, a stimulatorconfigured to produce coordinated limb movement, a cortical stimulator,a spinal cord stimulator, peripheral nerve stimulator, microstimulator,or in any other neural stimulator configured to treat urinaryincontinence, sleep apnea, shoulder subluxation, headache, etc.

Turning first to FIG. 1, an exemplary DBS neurostimulation system 10generally includes at least one implantable stimulation lead 12 (in thiscase, two), a neurostimulator in the form of an implantable pulsegenerator (IPG) 14, an external remote controller RC 16, a clinician'sprogrammer (CP) 18, an External Trial Stimulator (ETS) 20, and anexternal charger 22.

The IPG 14 is physically connected via one or more percutaneous leadextensions 24 to the neurostimulation leads 12, which carry a pluralityof electrodes 26 arranged in an array. In the illustrated embodiment,the neurostimulation leads 12 are percutaneous leads, and to this end,the electrodes 26 may be arranged in-line along the neurostimulationleads 12. In alternative embodiments, the electrodes 26 may be arrangedin a two-dimensional pattern on a single paddle lead if, e.g., corticalbrain stimulation is desired. As will be described in further detailbelow, the IPG 14 includes pulse generation circuitry that deliverselectrical stimulation energy in the form of a pulsed electricalwaveform (i.e., a temporal series of electrical pulses) to the electrodearray 26 in accordance with a set of stimulation parameters.

The ETS 20 may also be physically connected via the percutaneous leadextensions 28 and external cable 30 to the neurostimulation leads 12.The ETS 20, which has similar pulse generation circuitry as the IPG 14,also delivers electrical stimulation energy in the form of a pulseelectrical waveform to the electrode array 26 accordance with a set ofstimulation parameters. The major difference between the ETS 20 and theIPG 14 is that the ETS 20 is a non-implantable device that is used on atrial basis after the neurostimulation leads 12 have been implanted andprior to implantation of the IPG 14, to test the responsiveness of thestimulation that is to be provided. Thus, any functions described hereinwith respect to the IPG 14 can likewise be performed with respect to theETS 20.

The RC 16 may be used to telemetrically control the ETS 20 via abi-directional RF communications link 32. Once the IPG 14 andstimulation leads 12 are implanted, the RC 16 may be used totelemetrically control the IPG 14 via a bi-directional RF communicationslink 34. Such control allows the IPG 14 to be turned on or off and to beprogrammed with different stimulation parameter sets. The IPG 14 mayalso be operated to modify the programmed stimulation parameters toactively control the characteristics of the electrical stimulationenergy output by the IPG 14. As will be described in further detailbelow, the CP 18 provides clinician detailed stimulation parameters forprogramming the IPG 14 and ETS 20 in the operating room and in follow-upsessions.

The CP 18 may perform this function by indirectly communicating with theIPG 14 or ETS 20, through the RC 16, via an IR communications link 36.Alternatively, the CP 18 may directly communicate with the IPG 14 or ETS20 via an RF communications link (not shown). The clinician detailedstimulation parameters provided by the CP 18 are also used to programthe RC 16, so that the stimulation parameters can be subsequentlymodified by operation of the RC 16 in a stand-alone mode (i.e., withoutthe assistance of the CP 18).

The external charger 22 is a portable device used to transcutaneouslycharge the IPG 14 via an inductive link 38. For purposes of brevity, thedetails of the external charger 22 will not be described herein. Detailsof exemplary embodiments of external chargers are disclosed in U.S. Pat.No. 6,895,280, which has been previously incorporated herein byreference. Once the IPG 14 has been programmed, and its power source hasbeen charged by the external charger 22 or otherwise replenished, theIPG 14 may function as programmed without the RC 16 or CP 18 beingpresent.

Referring to FIG. 2, the IPG 14 comprises an outer case 40 for housingthe electronic and other components (described in further detail below),and a connector 42 to which the proximal end of the neurostimulationlead 12 mates in a manner that electrically couples the electrodes 26 tothe internal electronics (described in further detail below) within theouter case 40. The outer case 40 is composed of an electricallyconductive, biocompatible material, such as titanium, and forms ahermetically sealed compartment wherein the internal electronics areprotected from the body tissue and fluids. In some cases, the outer case40 may serve as an electrode.

Each of the neurostimulation leads 12 comprises an elongated cylindricallead body 43, and the electrodes 26 take the form of ring electrodesmounted around the lead body 43. One of the neurostimulation leads 12has eight electrodes 26 (labeled E1-E8), and the other neurostimulationlead 12 has eight electrodes 26 (labeled E9-E16). The actual number andshape of leads and electrodes will, of course, vary according to theintended application.

In an alternative embodiment illustrated in FIG. 3, the electrodes 26take the form of segmented electrodes that are circumferentially andaxially disposed about the lead body 43. By way of non-limiting example,and with further reference to FIG. 4, one neurostimulation lead 12 maycarry sixteen electrodes, arranged as four rings of electrodes (thefirst ring consisting of electrodes E1-E4; the second ring consisting ofelectrodes E5-E8; the third ring consisting of electrodes E9-E12; andthe fourth ring consisting of E13-E16) or four axial columns ofelectrodes (the first column consisting of electrodes E1, E5, E9, andE13; the second column consisting of electrodes E2, E6, E10, and E14;the third column consisting of electrodes E3, E7, E11, and E15; and thefourth column consisting of electrodes E4, E8, E12, and E16).

Further details describing the construction and method of manufacturingpercutaneous stimulation leads are disclosed in U.S. patent applicationSer. No. 11/689,918, entitled “Lead Assembly and Method of Making Same,”and U.S. patent application Ser. No. 11/565,547, entitled “CylindricalMulti-Contact Electrode Lead for Neural Stimulation and Method of MakingSame,” the disclosures of which are expressly incorporated herein byreference.

As will be described in further detail below, the IPG 14 includes abattery and pulse generation circuitry that delivers the electricalstimulation energy in the form of a pulsed electrical waveform to theelectrode array 26 in accordance with a set of stimulation parametersprogrammed into the IPG 14. Such stimulation parameters may compriseelectrode combinations, which define the electrodes that are activatedas anodes (positive), cathodes (negative), and turned off (zero),percentage of stimulation energy assigned to each electrode(fractionalized electrode configurations), and electrical pulseparameters, which define the pulse amplitude (measured in milliamps orvolts depending on whether the IPG 14 supplies constant current orconstant voltage to the electrode array 26), pulse duration (measured inmicroseconds), pulse rate (measured in pulses per second), and burstrate (measured as the stimulation on duration X and stimulation offduration Y). The IPG 14 may be capable of delivering the stimulationenergy to the array 22 over multiple channels or over only a singlechannel.

Electrical stimulation will occur between two (or more) activatedelectrodes, one of which may be the IPG case. Simulation energy may betransmitted to the tissue in a monopolar or multipolar (e.g., bipolar,tripolar, etc.) fashion. Monopolar stimulation occurs when a selectedone of the lead electrodes 26 is activated along with the case of theIPG 14, so that stimulation energy is transmitted between the selectedelectrode 26 and case. Bipolar stimulation occurs when two of the leadelectrodes 26 are activated as anode and cathode, so that stimulationenergy is transmitted between the selected electrodes 26. Multipolarstimulation occurs when at least three of the lead electrodes 26 areactivated, e.g., two as anodes and the remaining one as a cathode, ortwo as cathodes and the remaining one as an anode.

In the illustrated embodiment, IPG 14 can individually control themagnitude of electrical current flowing through each of the electrodes.In this case, it is preferred to have use current generators, whereinindividual current-regulated amplitudes from independent current sourcesfor each electrode may be selectively generated. Although this system isoptimal to take advantage of the invention, other stimulators that maybe used with the invention include stimulators having voltage regulatedoutputs. While individually programmable electrode amplitudes areoptimal to achieve fine control, a single output source switched acrosselectrodes may also be used, although with less fine control inprogramming. Mixed current and voltage regulated devices may also beused with the invention.

Further details discussing the detailed structure and function of IPGsare described more fully in U.S. Pat. Nos. 6,516,227 and 6,993,384,which are expressly incorporated herein by reference.

As shown in FIG. 5, two percutaneous neurostimulation leads 12 areintroduced through a burr hole 46 (or alternatively, two respective burrholes) formed in the cranium 48 of a patient 44, and introduced into theparenchyma of the brain 49 of the patient 44 in a conventional manner,such that the electrodes 26 are adjacent a target tissue region, thestimulation of which will treat the dysfunction (e.g., the ventrolateralthalamus, internal segment of globus pallidus, substantia nigra parsreticulate, subthalamic nucleus, or external segment of globuspallidus). Thus, stimulation energy can be conveyed from the electrodes26 to the target tissue region to change the status of the dysfunction.Due to the lack of space near the location where the neurostimulationleads 12 exit the burr hole 46, the IPG 14 is generally implanted in asurgically-made pocket either in the chest, or in the abdomen. The IPG14 may, of course, also be implanted in other locations of the patient'sbody. The lead extension(s) 24 facilitates locating the IPG 14 away fromthe exit point of the neurostimulation leads 12.

Referring now to FIG. 6, one exemplary embodiment of an RC 16 will nowbe described. As previously discussed, the RC 16 is capable ofcommunicating with the IPG 14, CP 18, or ETS 20. The RC 16 comprises acasing 50, which houses internal componentry (including a printedcircuit board (PCB)), and a lighted display screen 52 and button pad 54carried by the exterior of the casing 50. In the illustrated embodiment,the display screen 52 is a lighted flat panel display screen, and thebutton pad 54 comprises a membrane switch with metal domes positionedover a flex circuit, and a keypad connector connected directly to a PCB.In an optional embodiment, the display screen 52 has touchscreencapabilities. The button pad 54 includes a multitude of buttons 56, 58,60, and 62, which allow the IPG 14 to be turned ON and OFF, provide forthe adjustment or setting of stimulation parameters within the IPG 14,and provide for selection between screens.

In the illustrated embodiment, the button 56 serves as an ON/OFF buttonthat can be actuated to turn the IPG 14 ON and OFF. The button 58 servesas a select button that allows the RC 16 to switch between screendisplays and/or parameters. The buttons 60 and 62 serve as up/downbuttons that can actuated to increment or decrement any of stimulationparameters of the pulse generated by the IPG 14, including pulseamplitude, pulse width, and pulse rate. For example, the selectionbutton 58 can be actuated to place the RC 16 in an “Pulse AmplitudeAdjustment Mode,” during which the pulse amplitude can be adjusted viathe up/down buttons 60, 62, a “Pulse Width Adjustment Mode,” duringwhich the pulse width can be adjusted via the up/down buttons 60, 62,and a “Pulse Rate Adjustment Mode,” during which the pulse rate can beadjusted via the up/down buttons 60, 62. Alternatively, dedicatedup/down buttons can be provided for each stimulation parameter. Ratherthan using up/down buttons, any other type of actuator, such as a dial,slider bar, or keypad, can be used to increment or decrement thestimulation parameters. Further details of the functionality andinternal componentry of the RC 16 are disclosed in U.S. Pat. No.6,895,280, which has previously been incorporated herein by reference.

Referring to FIG. 7, the internal components of an exemplary RC 16 willnow be described. The RC 16 generally includes a controller/processor 64(e.g., a microcontroller), memory 66 that stores an operating programfor execution by the controller/processor 64, as well as stimulationparameter sets in a look-up table (described below), input/outputcircuitry, and in particular, telemetry circuitry 68 for outputtingstimulation parameters to the IPG 14 and receiving status informationfrom the IPG 14, and input/output circuitry 70 for receiving stimulationcontrol signals from the button pad 54 and transmitting statusinformation to the display screen 52 (shown in FIG. 6). As well ascontrolling other functions of the RC 16, which will not be describedherein for purposes of brevity, the controller/processor 64 generatesnew stimulation parameter sets in response to the user operation of thebutton pad 54. These new stimulation parameter sets would then betransmitted to the IPG 14 (or ETS 20) via the telemetry circuitry 68.Further details of the functionality and internal componentry of the RC16 are disclosed in U.S. Pat. No. 6,895,280, which has previously beenincorporated herein by reference. Notably, while thecontroller/processor 64 is shown in FIG. 7 as a single device, theprocessing functions and controlling functions can be performed by aseparate controller and processor.

As briefly discussed above, the CP 18 greatly simplifies the programmingof multiple electrode combinations, allowing the physician or clinicianto readily determine the desired stimulation parameters to be programmedinto the IPG 14, as well as the RC 16. Thus, modification of thestimulation parameters in the programmable memory of the IPG 14 afterimplantation is performed by a clinician using the CP 18, which candirectly communicate with the IPG 14 or indirectly communicate with theIPG 14 via the RC 16. That is, the CP 18 can be used by the physician orclinician to modify operating parameters of the electrode array 26 inthe brain.

The overall appearance of the CP 18 is that of a laptop personalcomputer (PC), and in fact, may be implanted using a PC that has beenappropriately configured to include a directional-programming device andprogrammed to perform the functions described herein. Alternatively, theCP 18 may take the form of a mini-computer, personal digital assistant(PDA), smartphone, etc., or even a remote control (RC) with expandedfunctionality. Thus, the programming methodologies can be performed byexecuting software instructions contained within the CP 18.Alternatively, such programming methodologies can be performed usingfirmware or hardware. In any event, the CP 18 may actively control thecharacteristics of the electrical stimulation generated by the IPG 14 toallow the optimum stimulation parameters to be determined based onpatient response and feedback and for subsequently programming the IPG14 with the optimum stimulation parameters.

Referring to FIG. 8, to allow the user to perform these functions, theCP 18 includes a standard user input device 72 (e.g., a keyboard, mouse,joystick, etc.) to allow a clinician to input information and controlthe process and a display monitor 76 housed in a case. In theillustrated embodiment, the monitor 76 is a conventional screen.Alternatively, instead of being conventional, the monitor 76 may be adigitizer screen, such as touchscreen (not shown), and may be used inconjunction with an active or passive digitizer stylus/finger touch. TheCP 18 generally includes a controller/processor 80 (e.g., a centralprocessor unit (CPU)) and memory 82 that stores a stimulationprogramming package 84, which can be executed by thecontroller/processor 80 to allow the user to program the IPG 14, and RC16. The CP 18 further includes output circuitry 86 for downloadingstimulation parameters to the IPG 14 and RC 16 and for uploadingstimulation parameters already stored in the memory 66 of the RC 16, viathe telemetry circuitry 68 of the RC 16. Notably, while thecontroller/processor 80 is shown in FIG. 8 as a single device, theprocessing functions and controlling functions can be performed by aseparate controller and processor. Thus, it can be appreciated that thecontrolling functions described below as being performed by the CP 18can be performed by a controller, and the processing functions describedbelow as being performed by the CP 18 can be performed by a processor.

Execution of the programming package 84 by the controller/processor 80provides a multitude of display screens (not shown) that can benavigated through via use of the user input device 72. These displayscreens allow the clinician to, among other functions, to select orenter patient profile information (e.g., name, birth date, patientidentification, physician, diagnosis, and address), enter procedureinformation (e.g., programming/follow-up, implant trial system, implantIPG, implant IPG and lead(s), replace IPG, replace IPG and leads,replace or revise leads, explant, etc.), generate a therapeutic map(e.g., body regions targeted for therapy, body regions for minimizationof side-effects, along with metrics (e.g., Unified Parkinson's DiseaseRating Scale (UPDRS)) of success for said targets) of the patient,define the configuration and orientation of the leads, initiate andcontrol the electrical stimulation energy output by the leads 12, andselect and program the IPG 14 with stimulation parameters in both asurgical setting and a clinical setting. Further details discussing theabove-described CP functions are disclosed in U.S. patent applicationSer. No. 12/501,282, entitled “System and Method for Converting TissueStimulation Programs in a Format Usable by an Electrical CurrentSteering Navigator,” and U.S. patent application Ser. No. 12/614,942,entitled “System and Method for Determining Appropriate Steering Tablesfor Distributing Stimulation Energy Among Multiple NeurostimulationElectrodes,” which are expressly incorporated herein by reference.

The user interface includes a series of programming screens with variouscontrol elements that can be actuated to perform functions correspondingto the control elements. In the illustrated embodiment, control elementsare implemented as a graphical icon that can be clicked with a mouse inthe case of a conventional display device. Alternatively, the displaydevice may have a digitizer screen (e.g., a touchscreen) that can betouched or otherwise activated with an active or passive digitizerstylus. More alternatively, the control elements described herein may beimplemented as a joy stick, touchpad, button pad, group of keyboardarrow keys, mouse, roller ball tracking device, horizontal or verticalrocker-type arm switches, etc., that can be pressed or otherwise movedto actuate the control elements. Alternatively, other forms of enteringinformation can be used, such as textual input (e.g., text boxes) ormicrophones.

In particular, a programming screen 100 can be generated by the CP 18,as shown in FIG. 9. The programming screen 100 allows a user to performstimulation parameter testing. To this end, the programming screen 100comprises a stimulation on/off control 102 that can be alternatelyclicked to turn the stimulation on or off. The programming screen 100further includes various stimulation parameter controls that can beoperated by the user to manually adjust stimulation parameters. Inparticular, the programming screen 100 includes a pulse width adjustmentcontrol 104 (expressed in microseconds (μs)), a pulse rate adjustmentcontrol 106 (expressed in pulses per second (pps), and a pulse amplitudeadjustment control 108 (expressed in milliamperes (mA)). Each controlincludes a first arrow that can be clicked to decrease the value of therespective stimulation parameter and a second arrow that can be clickedto increase the value of the respective stimulation parameter. Theprogramming screen 100 also includes multipolar/monopolar stimulationselection control 110, which includes check boxes that can bealternately clicked by the user to provide multipolar or monopolarstimulation. In an optional embodiment, the case 40 of the IPG 14 may betreated as one of the lead electrodes 26, such that both the caseelectrode 40 and at least one of the lead electrodes 26 can be used toconvey anodic electrical current at the same time. Additionally, thecase electrode may be configured with all the programmability of a leadelectrode, with full anodic and cathodic fractionalization.

The programming screen 100 also includes an electrode combinationcontrol 112 having arrows that can be clicked by the user to select oneof four different electrode combinations 1-4. Each of the electrodecombinations 1-4 can be created using a variety of control elements. Theprogramming screen 100 also includes a set of axial electricalstimulation field displacement control elements 116 and a set of axialelectrical stimulation field shaping control elements 118.

When any of the axial electrical stimulation field displacement controlelements 116 is actuated, control signals are generated in response towhich the controller/processor 80 is configured for generatingstimulation parameter sets designed to axially displace the locus of theelectrical stimulation field relative to the axis of the lead 12.Preferably, the control signals that are generated in response to theactuation of the axial electrical stimulation field displacement controlelements 116 or the alternative control elements are directional,meaning that the locus of the electrical stimulation field will bedisplaced in a defined direction in response to a continual actuation ofa single control element irrespective of the current position of thelocus electrical stimulation field locus. When any of the axialelectrical stimulation field shaping control elements 118 is actuated,control signals are generated in response to which thecontroller/processor 80 is configured for generating stimulationparameter sets designed to axially expand or contract the electricalstimulation field relative to its locus.

The control elements 116, 118 may be continually actuated (i.e., bycontinuously actuating one of the control elements 116, 118, e.g., byclicking on one of the control elements 116, 118 and holding the click(i.e., continuous actuation of the control following the initial“click”), or repeatedly actuating one of the control elements 116, 118,e.g., by repeatedly clicking and releasing one of the control elements116, 118) to generate a series of control signals in response to whichthe controller/processor 80 is configured for generating the pluralityof stimulation parameter sets. The output telemetry circuitry 86 isconfigured for transmitting these stimulation parameters sets to the IPG14.

Each of the sets of control elements 116, 118 takes the form of a doublearrow (i.e., two oppositely pointing control element arrows) that can beactuated to modify the electrical stimulation field depending on themode of operation. For example, an upper arrow control element 116 a canbe clicked to axially displace the locus of the electrical stimulationfield (i.e., along the axis of the lead 12) in the proximal direction; alower arrow control element 116 b can be clicked to axially displace thelocus of the electrical stimulation field (i.e., along the axis of thelead 12) in the distal direction; a lower arrow control element 118 acan be clicked to axially contract the electrical stimulation fieldabout its locus, and an upper arrow control element 118 b can be clickedto axially expand the electrical stimulation field about its locus.

The locus of the electrical stimulation field may be displaced, e.g., bygradually “steering” or shifting electrical current between electrodesin a single timing channel. For example, the locus of the electricalstimulation field can be gradually displaced axially in the distaldirection along the lead 12 by gradually including electrodes in astimulating electrode group and gradually excluding other electrodesfrom the stimulating electrode group in the single timing channel.

Although the programming screen 100 illustrates only oneneurostimulation lead 12 with electrodes arranged in only one dimension,thereby allowing the electrical current to only be steered in onedimension, it should be appreciated that the programming screen 100 mayadditionally illustrate the other neurostimulation lead 12, therebyarranging the electrodes in two dimensions and allowing the electricalcurrent to be steered in two dimensions. In this case, using appropriatecontrol elements (e.g., left and right arrows), the locus of theelectrical stimulation field can be displaced in the transversedirection (perpendicular to the axial direction, and in this case, leftor right) and/or the electrical stimulation field can be expanded orcontracted in the transverse direction. Of course, the electrodes can bearranged in three-dimensions (e.g., by arranging three neurostimulationleads in three-dimensions or by using electrodes on a singleneurostimulation lead that are arranged in three-dimensions, e.g., thesegmented neurostimulation leads described in U.S. Provisional PatentApplication Ser. No. 61/374,879), in which case, the electrical currentcan be steering in three-dimensions.

Further details discussing different techniques for modifying anelectrical stimulation field is disclosed in U.S. Provisional PatentApplication 61/374,879, entitled “User Interface for SegmentedNeurostimulation Leads,” which is expressly incorporated herein byreference. In an optional embodiment where the neurostimulation lead 12with segmented electrodes 26 (see FIG. 3) are used, additional controlelements can be provided to circumferentially displace the locus of theelectrical stimulation field, circumferentially contract or expand theelectrical stimulation field, radially displace the locus of theelectric field, or radially contract or expand the electricalstimulation field, as disclosed in U.S. Provisional Patent Application61/374,879.

The programming screen 100 displays three-dimensional graphicalrenderings of the lead 12′ and electrodes 26′. In an optionalembodiment, iconic control elements 120 are graphically linked to thethree-dimensional electrode renderings 26′. Continual actuation of thecontrol elements 120 generates control signals that prompt thecontroller/processor 80 to generate stimulation parameters designed tomodify the electrical stimulation field, which stimulation parametersare then transmitted from the output circuitry 86 of the CP 18 to theIPG 14. In the illustrated embodiment, each of the control elements 120has an up arrow and a down arrow that can be respectively actuated(e.g., by clicking) to respectively increase or decrease the electricalcurrent flowing through the electrode 26 corresponding to the graphicalelectrode rendering 26′ to which the actuated control element 120 isgraphically linked.

Actuation of any of the control elements 120 essentially steerselectrical current from other active electrodes to the electrodeassociated with the actuated control element 120 or from the electrodeassociated with the actuated control element 120 to other activeelectrodes. In this manner, the locus of the electrical stimulationfield can be displaced, the shape of the electrical stimulation fieldcan be modified, and if two separate electrical stimulation fieldscurrent exist, electrical current can be shifted from one of theelectrical stimulation fields (effectively decreasing its size) toanother of the electrical stimulation fields (effectively increasing itssize).

The control element 120 also includes an indicator 122 that provides anindication of the amount of electrical current flowing through each ofthe electrodes 26 in terms of a fractionalized current value. Theindicators 122 may perform this function when the respective controlelements 120 are actuated or when the axial electrical stimulation fielddisplacement control elements 116 and axial electrical stimulation fieldshaping control elements 118 are actuated.

The programming screen 100 displays the three-dimensional graphicalrenderings of the lead 12′ and electrodes 26′ in registration withanatomical regions of interest, and in particular, a therapy tissueregion 124, the stimulation of which is known or believed to provide theneeded therapy to the patient, and a side-effect tissue region 126, thestimulation of which is known or believed to provide an undesirableside-effect for the patient. The anatomical regions of interest may beanatomical structures, the boundaries of which are naturally defined, ormay be arbitrary volumes of interest known to result in therapy or aside-effect when stimulated. In the illustrated embodiment, theanatomical regions of interest are obtained from a generally availableatlas. In the illustrated embodiment, the anatomical regions of interestare shown as being two-dimensional, although in other embodiments, theanatomical regions of interest may be three-dimensional in nature.

Based on the current stimulation parameter set, the CP 18 may estimateof a resulting region of tissue activation (RTA) 128, which can bedisplayed on the programming screen 100 with the graphical lead 12′ andanatomical regions of interest 124, 126. Further details discussingtechnique for computing the estimate of a RTA 128 are disclosed in A. M.M. Frankemolle, et al., Reversing Cognitive-Motor Impairments inParkinson's Disease Patients Using a Computational Modelling Approach toDeep Brain Stimulation Programming, Brain 2010; pp. 1-16), which isexpressly incorporated herein by reference.

Alternatively, instead of computing and displaying a RTA, the CP 18 maycompute an electric field (not shown) from the current stimulationparameter set, which may be displayed relative to the graphical lead 12′and anatomical regions of interest 124,126. In the illustratedembodiment, although the graphical lead 12′, anatomical regions ofinterest 124,126, and the RTA 128 are displayed in an oblique view, theycan be alternatively displayed in any one or more of traditional planesof section (e.g., axial, coronal, and sagittal.

Most pertinent to the present inventions, execution of the programmingpackage 84 provides a more intuitive user interface that allows a userto readily determine the extent that to which specified electrodesinfluence one or more clinical effects (e.g., a therapeutic effectand/or side-effect), modify anatomical regions of interest (e.g., atherapy tissue region and/or a side-effect tissue region) to be specificto the patient, and/or matching a electric field, and thus the electrodecombination that best generates the electric field, to a therapy tissueregion. To this end, the user interface allows the user to select one ormore brain disorders to be treated (FIG. 10), perform a clinicalanalysis to determine the extent to which each of the electrodes 26influences anatomical regions of interest (FIGS. 11-12, 15-16, and19-20), determine the shape and/or boundaries of target and non-targettissue regions (FIGS. 13-14 and 17-18), optionally modify the shapeand/or location of anatomical regions of interest (FIGS. 21-24),determining the shape of the electric field that best matches the targettissue region(s) (FIGS. 25-28), determining the program that bestemulates the shape of the electric field (FIG. 29), and programming theIPG 14/RC 16 with the selected program.

As shown in FIG. 10, a therapy selection screen 200, which allows a userto select one or more brain disorders to be treated, can be initiallygenerated by the CP 18. In particular, the therapy selection screen 200includes graphical controls in the form of a series of disorder boxes202 a, 202 b, 202 c that can be clicked to select the brain disorder tobe treated. In the illustrated embodiment, the disorder box 202 a can beclicked to treat Parkinson's Disease, the disorder box 202 b can beclicked to treat Essential Tremor, and the disorder box 202 c can beclicked to treat Dystonia. Additional disorder boxes may be displayed inthe therapy selection screen 200, so that other types of brain disorderscan be treated. Default stimulation parameters, and in this case, adefault pulse width and pulse rate, for each disorder to be treated areshown below the respective disorder box 202. In the illustratedembodiment, a default pulse width of 60 μs and a default pulse rate of130 Hz is shown for treatment of the Parkinson's Disease, a defaultpulse width of 120 μs and a default pulse rate of 130 Hz is shown forthe treatment of Essential Tremor, and a default pulse width of 250 μsand a default pulse rate of 130 Hz is shown for the treatment ofDystonia. The default pulse width and default pulse rate, as well as thepulse amplitude, can be varied by the user using the programming screen100. More than one of the disorder boxes can be clicked to treatmultiple brain disorders. The therapy selection screen 200 furtherincludes a next button 204 that can be clicked to continue to the nextscreens described below.

Significantly, the CP 18 can be used to instruct the IPG 14 to seriallyconvey electrical stimulation energy into the tissue via differentcombinations of the electrodes 26, thereby creating one or more clinicaleffects for each of the different electrode combinations. For example,assuming that a neurostimulation lead 12 is implanted in tissuecontaining a first therapy region TH1 (e.g., one the stimulation ofwhich alleviates or eliminates the symptoms of Parkinson's Disease), asecond therapy region TH2 (e.g., one the stimulation of which alleviatesor eliminates the symptoms of Dystonia), a first side-effect region SE1(e.g., one the stimulation of which causes nausea), and a secondside-effect region SE2 (e.g., one the stimulation of which causesheadache), as shown in FIG. 11, conveyance of electrical stimulationenergy via different combinations of the electrodes will cause either atherapeutic effect, a side-effect, or both.

The CP 18 quantifies the influence of each of the different electrodecombinations on the clinical effects. For example, if electrode E1 isactivated to convey electrical stimulation energy, it may be concludedthat this electrode somewhat influences the side-effect associated withthe first side-effect region SE1. If electrode E2 is activated to conveyelectrical stimulation energy, it may be concluded that this electrodesomewhat influences the therapeutic effect associated with the firsttherapy region TH1 and the side-effect associated with the firstside-effect region SE1. If electrode E3 is activated to conveyelectrical stimulation energy, it may be concluded that this electrodehighly influences the therapeutic effect associated with the firsttherapy region TH1. If electrode E4 is activated to convey electricalstimulation energy, it may be concluded that this electrode highlyinfluences therapeutic effects associated with the first and secondtherapy regions TH1, TH2. If electrode E5 is activated to conveyelectrical stimulation energy, it may be concluded that this electrodesomewhat influences a side-effect associated with the second side-effectregion SE2 and therapeutic effects associated with the first and secondtherapy regions TH1, TH2. If any of electrodes E6-E8 is activated toconvey electrical stimulation energy, it may be concluded that theseelectrodes highly influence a side-effect associated with the secondside-effect region SE2.

In the preferred embodiment, the intensity level of the electricalstimulation energy conveyed via each electrode combination isincrementally varied, such that the influence by a specific electrodecombination on the clinical effects can be determined by the CP 18 foreach of the different intensity levels. The influence by a specificelectrode combination on the clinical effects can be determined by theCP 18, e.g., based on clinical information entered by the user. Forexample, as described in further detail below, the user may enter intothe CP 18 the intensity level at which the patient experiences atherapeutic effect or a side-effect for the specific electrodecombination. Alternatively, the influence by a specific electrodecombination on the clinical effects can be determined by the CP 18,e.g., based on monitored clinical information automatically provided tothe CP 18 from monitoring circuitry (not shown).

As will be described in further detail below with respect to variousembodiments, once the influences of each electrode combination on theclinical effects have been determined, the CP 18 can then generate anddisplay graphical indications of these determined influences, such thatthe user can determine an extent to which each of the differentelectrode combinations influences the clinical effects. For the purposesof this specification, the term “graphical” means a textual ornon-textual representation. Although the embodiments described hereindisplay non-textual representations of the determined influences, whichprovides a readily understandable visual from which the user maydetermine the extent to which each of the different electrodecombinations influences the clinical effects, textual representations ofthe determined influences can be used in addition to, or alternative, tothe non-textual graphical indications of the determined influences.

In one embodiment shown in FIG. 12, a clinical effect analysis screen300 allows a user to readily determine the extent to which each of thedifferent electrode combinations influences the clinical effects. Inparticular, the clinical effect analysis screen 300 includes anintensity level adjustment control 302, which includes an upper arrow302 a that can be clicked to increase the intensity value of theelectrical stimulation energy conveyed via a specified electrodecombination, and a lower arrow 302 b that can be clicked to decrease theintensity value of the electrical stimulation energy conveyed via aspecified electrode combination. The intensity level adjustment control302 also includes an indicator 302 c that provides an indication of theintensity of the conveyed electrical stimulation energy, and in theillustrated embodiment, the amount of electrical current flowing througha specified electrode combination in milliamperes. In the illustratedembodiment, the range of intensity values that can be selected is 0-5 mAin one milliampere increments, although in other embodiments, the rangeof intensity values may be larger or smaller, or have a higher or lowerresolution. The pulse width and pulse rate of the conveyed electricalstimulation energy will correspond to the default parameters of thedisorder selected to be treated in the therapy selection screen 200. Inan optional embodiment, the clinical effect analysis screen 300 mayinclude a pulse width adjustment control and a pulse rate adjustmentcontrol (not shown) similar to the adjustment controls 104 and 106described above with respect to FIG. 9, so that the pulse width and/orpulse rate of the conveyed electrical stimulation energy may be adjustedfrom their default values.

The clinical effect analysis screen 300 also includes a graphicalrepresentation of the neurostimulation lead 12′ and correspondingelectrodes 26′. In the illustrated embodiment, only the graphicalrepresentation for one neurostimulation lead 12′ having electrodes E1-E8is displayed, although graphical representations for multipleneurostimulation leads 12 or alternative neurostimulation leads (e.g.,the segmented neurostimulation lead illustrated in FIG. 3) can bedisplayed.

The clinical effect analysis screen 300 also includes an electrodeselection control 304 that can be used to select the specific electrodecombination to be currently tested (i.e., the specific electrodecombination through which the electrical stimulation energy will flow).In the illustrated embodiment, each electrode combination has a singleelectrode. To this end, the electrode selection control 304 includes anupper arrow 304 a that can be clicked to increase the index number ofthe electrode 26, and a lower arrow 304 b that can be clicked todecrease the index number of the electrode 26. The electrode selectioncontrol 304 also includes an indicator 304 c that provides an indicationof the selected electrode 26. In the illustrated embodiment, electricalstimulation energy is conveyed through each selected electrode 26 in amonopolar manner.

The clinical effect analysis screen 300 further includes clinicalinformation entry buttons 306 that allows the user to enter clinicalinformation, and in this embodiment, a therapeutic effect trigger button306 a that can be actuated when the patient experiences a therapeuticeffect, and a side-effect trigger button 306 b that can be actuated whenthe patient experiences a side-effect. Verbal feedback from the patientmay prompt the user to actuate either of the clinical information entrybuttons 306. A therapeutic effect may be considered to be a mitigationof a symptom (or a component of the symptom) caused by a disorder,whereas a side-effect can be considered a symptom (or a component of thesymptom) of the electrical stimulation. The CP 18 will be capable ofdetermining the influence of each electrode 26 on the therapeutic andside-effects based on the clinical information entered by the user viathe clinical information entry buttons 306.

In this embodiment, the CP 18 quantifies the influence of each electrode26 on the therapeutic effect by determining the range of incrementalintensity levels at which a metric of a therapeutic effect occurs basedon clinical information entered by the user via the clinical informationentry buttons 306, and further determining the incremental intensitylevel at which a metric of a side-effect initially occurs. In thisembodiment, the metric of the therapeutic effect is an absolute metric,and in particular, whether the perception threshold of the therapeuticeffect has been reached or exceeded, and the metric of the side-effectis also an absolute metric, and in particular, whether the perceptionthreshold of the therapeutic effect has been reached or exceeded.

In the illustrated embodiment, for each activated electrode, theintensity level adjustment control 302 can be manipulated toincrementally increase the intensity level of the electrical stimulationenergy, and at each intensity level, the patient may provide feedback asto whether a therapeutic effect or a side-effect is experienced. Forexample, for electrode E1, the intensity level of the electricalstimulation energy can be incrementally increased, with the patientproviding feedback at each of the incremental intensity levels; forelectrode E2, the intensity level of the electrical stimulation energycan be incrementally increased, with the patient providing feedback ateach of the incremental intensity levels; and so on.

Thus, at each intensity level for each activated electrode, the user mayactuate the therapeutic effect trigger button 306 a if the therapeuticeffect is perceived at all by the patient, and may actuate theside-effect trigger button 306 b if a side-effect is perceived at all bythe patient, such that the CP 18 may determine the range of intensitylevels at which the perception threshold of the therapeutic effect ismet or exceeded and the intensity level at which the perceptionthreshold of the side-effect is initially met or exceeded for eachactivated electrode. Preferably, in the case where the patient hasmultiple disorders to be treated, the user will actuate the therapeuticeffect trigger button 306 a if a therapeutic effect associated with anyof the multiple disorders is perceived, even though a therapeutic effectassociated with other multiple disorders may not be perceived.

In other embodiments, the metric of the therapeutic effect may be, e.g.,whether a relative level (e.g., a particular comfort level) of thetherapeutic effect has been reached or exceeded, and the metric of theside-effect may be, e.g., whether a relative level (e.g., an annoyancelevel or an intolerable level) has been reached or exceeded. As will bedescribed in other embodiments below, the metric of the therapeuticeffect and/or side-effect may take the form of a score that can beseparately assigned to a therapeutic effect or side-effect or a wellnessscore that takes into account both the therapeutic effect or theside-effect.

Based on the clinical information entered by the user (in thisembodiment, by pushing the therapeutic effect trigger button 306 a orthe side-effect trigger button 306 b at the appropriate times), the CP18 may determine the highest intensity level at which the therapeuticeffect occurs prior to the initial occurrence of a side-effect. The CP18 may then graphically generate and display this information in theform of a bar map 308 having a plurality of bars 310, each of whichindicates for each of the electrodes E1-E8 the highest intensity levelat which a therapeutic effect occurs prior to the initial occurrence ofthe side-effect. The horizontal axis of the bar map represents intensitylevel in increments of one milliamp here, and the vertical axis of thebar map represents the electrode number.

In the case where there is at least one intensity level at which thetherapeutic effect occurs prior to the initial occurrence of aside-effect, the bar 310 will be a particular color (e.g., green)indicating the range of the intensity levels at which the therapeuticeffect occurs. A first tick 312 (e.g., green color) can be placed at thebeginning of the bar 310, indicating the intensity level at which thetherapeutic effect initially occurs, and a second tick 314 (e.g., redcolor) can be placed on the bar 310, indicating the intensity level atwhich the side-effect initially occurs. In the case where there is nointensity level at which the therapeutic effect occurs prior to theinitial occurrence of the side-effect (i.e., the side-effect occursprior to the therapeutic effect). In this case where an electrode hasnot been tested, a question mark “?” is displayed next to thatelectrode.

For example, as shown in FIG. 12 and with further reference to FIG. 11,only a side-effect tick 314 is displayed adjacent electrode E1,indicating that a side-effect was perceived prior to a therapeuticeffect. Viewing this, a user may understand electrode E1 to highlyinfluence a side-effect region without influencing a therapeutic effectat all, which corresponds to electrode E1 being partially contained inthe first side-effect region SE1. The relatively short bar 310 displayedadjacent electrode E2 (in the range of 1 mA-2 mA) indicates to the userthat electrode E2 somewhat influences a therapeutic effect and aside-effect, which corresponds to electrode E2 being between the firsttherapy region TH1 and the first side-effect region SE1. The relativelylong bar 310 displayed adjacent electrode E3 (in the range of 1 mA-4 mA)indicates to the user that electrode E3 highly influences a therapeuticeffect, which corresponds to electrode E3 being fully within the firsttherapy region TH1. The longer bar 310 displayed adjacent electrode E4(in the range of 1 mA-5 mA) indicates to the user that electrode E4influences a therapeutic effect the most out of all of the electrodes,which corresponds to electrode E4 being in the center of the firsttherapy region TH1. The relatively moderate length bar 310 displayedadjacent electrode E5 (in the range of 1 mA-3 mA) indicates to the userthat electrode E5 somewhat influences a therapeutic effect and a sideeffect, which corresponds with electrode E5 being partially contained inthe first and second therapy regions TH1, TH2, and near the secondside-effect region SE2. Only a side-effect tick 314 is displayedadjacent electrode E6, indicating that electrode E6 to highly influencea side-effect region without influencing a therapeutic effect at all,which corresponds to electrode E6 being contained in the secondside-effect region SE1. The question marks adjacent electrodes E7 and E8have not been tested, presumably by choice of the user based on the factthat the therapeutic effect substantially diminished at electrode E6.

Although this embodiment has been described as activating each of theelectrodes E1-E8 to either an “on” state (100% of the stimulation energyis provided by the electrode) or an “off” state (0% of the stimulationenergy is provided by the electrode), in effect, allowing the electrodesto be sequentially turned on and off up or down the neurostimulationlead 12, electrical current can be steered along the neurostimulationlead 12, such that a plurality of the electrodes can have fractionalizedcurrent values. For example, electrical current can be steered up ordown the neurostimulation lead 12 in 10% increments by, e.g., clickingthe up and down arrows of a control mechanism similar to the electrodeselection control 304.

For example, the process may start with 100% of the electrical currentat electrode E1, then 90% of the electrical current at electrode E1 and10% of the electrical current at electrode E2, then 80% of theelectrical current at electrode E1 and 20% of the electrical current atelectrode E2, and so forth, until a sufficient number of electrodes havebeen tested. At each fractionalized electrode combination, the user mayincrementally increase the intensity level of the stimulation energy inthe manner discussed above, so that clinical information can be obtainedfor each fractionalized electrode combination. A bar map can begenerated in the same manner discussed above, with the exception thatthere will be many more bars (one for each fractionalized electrodecombination).

In any event, with knowledge that electrode E4 and the adjacentelectrodes influence a therapeutic effect, the user may accordinglyprogram the IPG 14 with the appropriate electrode combination. In oneembodiment, the CP 18 dynamically generates and displays the bar map 308as the user enters the clinical information via the clinical triggerbuttons 306. In an alternative embodiment, the CP 18 generates anddisplays the bar map 308 only after the user has entered all of theclinical information necessary to complete the bar map 308, e.g., whenprompted by the user via a control button (not shown). The bar map 308is preferably stored in memory 82 for use in a subsequent programmingsession, which may be fully manually performed by the user or may beautomated by the CP 18. Optionally, the bar map 308 may be displayed andstored in memory 82 for other purposes. For example, the bar map 308 maybe displayed in a report or on another device, in a database (e.g., forpopulation analysis), or in a computer file that could be used byanother application.

The clinical effect analysis screen 300 further includes a disordertreatment indicator 316 that provides an indication to the user of thecurrent disorder that is being treated (i.e., the disorder selected inthe therapy selection screen 200 illustrated in FIG. 10). This indicatorcan be stored with the bar map 308 in memory 82, such that the user mayknows the treated disorder to which the bar map 308 corresponds whensubsequently recalled from memory 82. It should also be appreciated thatif multiple disorders are treated, several bar maps 308 may begenerated, displayed, and stored in memory, one bar map 308 for eachdisorder to be treated. For example, after generating, displaying, andstoring a bar map 308 for one disorder, the user can return to thetherapy selection screen 200, select another disorder via the disorderboxes 202, and then go to the clinical effects analysis screen 300 toprompt the CP 18 to generate, display, and store another bar map 308 forthe new disorder to be treated.

In an optional embodiment, the bar map 308 is used by the CP 18 todefine and display a target tissue region for stimulation. Inparticular, as shown in FIG. 13, the CP 18 may automatically define aline 318(1) that connects relevant points 320 within the bars 310 of thebar map 308. In the illustrated embodiment, these points 320 are locatedhalfway between the initial intensity levels of the therapeutic effects(to the extent that there is a therapeutic intensity level) and theside-effect ticks 314 indicated in the respective bars 310 of the barmap 308.

The CP 18 may then smooth the line 318(1) and revolve it around avertical axis 322 defined by the electrodes to create a bi-laterallysymmetrical target tissue region 324(1), as shown in FIG. 14, which canbe displayed to the user to aid in programming the IPG 14. In the case,where a three-dimensional target tissue region is generated anddisplayed, the line 318(1) is revolved around the vertical axis 322 ofthe electrodes to define a three-dimensional volume. Although the targettissue region 324 may not identically match the therapy regions TH1, TH2illustrated in FIG. 11, it still provides a suitable visual guide forthe user to facilitate the programming of the IPG 14 with one or moreeffective electrode combinations.

In alternative embodiments, the connecting points 320 may be located atother locations in the bar map 308, such as, e.g., at the end of thebars 310 (i.e., at the highest intensity levels of the therapeuticeffect) or three-quarters between the initial intensity levels of thetherapeutic effects (to the extent that there is a therapeutic intensitylevel) and the side-effect ticks 314 indicated in the respective bars310 of the bar map 308. In these cases, the CP 18 may automaticallydefine line 318(2) and 318(2) that connect the relevant points 320within the bars 310 of the bar map 308, smooth the lines 318(2) and318(3), and revolve them around the vertical axis 322 defined by theelectrodes to respectively create bi-laterally symmetrical target tissueregions 324(2) and 324(3), as shown in FIG. 14.

Notably, the line 318(1) and the corresponding target tissue region324(1) provides the least aggressive therapy (e.g., when the patient isasleep), the line 318(2) and the corresponding target tissue region324(2) provides moderately aggressive therapy (e.g., when the patient istalking), and the line 318(3) and the corresponding target tissue region324(3) provides the most aggressive therapy (e.g., when the patient iswalking). A control (not shown) can be provided, which can be actuatedby the user to select a “low” setting that prompts the CP 18 to createtarget tissue regions having the least aggressive therapy, a “medium”setting that prompts the CP 18 to create target tissue regions having amoderately aggressive therapy, and a “high” setting that prompts the CP18 to create target tissue regions having the most aggressive therapy.

Although the previous embodiment has been described in the context of aneurostimulation lead 12 having ring electrodes 26 (e.g., theneurostimulation lead 12 illustrated in FIG. 2), a neurostimulation lead12 having segmented electrodes 26 can be used (e.g., theneurostimulation lead 12 illustrated in FIG. 3).

For example, referring to FIGS. 15a-15d , a clinical effect analysisscreen 400 allows a user to readily determine the extent to which eachof the different electrode combinations influences the clinical effects.The clinical effect analysis screen 400 is similar to the clinicaleffect analysis screen 300 illustrated in FIG. 12, with the exceptionthat a bar map 308 is generated and displayed for the electrode segments26 on one side of the neurostimulation lead 12 (i.e., a first bar map308 a for electrodes E1, E5, E9, and E13 (FIG. 15a ); a second bar map308 b for electrodes E2, E6, E10, and E14 (FIG. 15b ); a third bar map308 c for electrodes E3, E7, E11, and E15 (FIG. 15c ); and a fourth barmap 308 d for electrodes E4, E8, E12, and E16 (FIG. 15d )). In the samemanner discussed above with respect to the clinical effect analysisscreen 300, the intensity level of the electrical stimulation energyconveyed through each electrode can be incrementally increased using theintensity level adjustment control 302, and the clinical information canbe gathered via the clinical effect trigger buttons 306, such that thebar maps 308 can be generated. However, the clinical effect analysisscreen 400 includes a view rotation button 424 that rotates the view ofthe electrodes 26 and corresponding bar map 308 in a carousel-likefashion. In an optional embodiment where the generation and display of atarget tissue region is desired, the CP 18, for each bar map 308, maydefine a line that connects relevant points within the bars 310, suchthat a total of four lines spaced 90 degrees from each other aredefined. In this case, the CP 18 may conform a three-dimensional surfaceto the lines to create a three-dimensional target tissue region.

As briefly discussed above, instead of entering clinical informationindicating whether or not a therapeutic effect or side-effect has beenperceived by the patient, as score can be assigned to a therapeuticeffect or even a side-effect to allow the CP 18 to better quantify theclinical effects. The use of scores to aid in determining clinicaleffects is particularly useful when multiple disorders are being treatedfor the patient.

For example, referring to FIG. 16, a clinical effect analysis screen 500is similar to the clinical effect analysis screen 300 described above,with the exception that, instead of having clinical trigger buttons 306that allow the user to enter when a therapeutic effect or side-effect isperceived, this screen includes score entry boxes 506, and inparticular, a therapeutic score box 506 a and a side-effect score box506 b, that allows the user to enter scores for the therapeutic effector side-effect. Thus, for each incremental intensity level of theelectrical stimulation energy conveyed via the currently selectedelectrode, the user may enter a score for a therapeutic effect (if any)in the therapeutic score box 506 a, and a score for a side-effect (ifany) in the side-effect score box 506 b.

Of course, a different means for entering scores into the CP 18 anddisplaying the scores to the user other than text entry boxes can beused, controls similar to the intensity level adjustment control 302 andelectrode selection control 304. Whereas the user preferablyincrementally increased the intensity level of the stimulation energyvia the intensity level adjustment control 302 until a side-effect wasperceived (i.e., up until the perception threshold of the side-effect ismet or exceeded) in the clinical effects analysis screen 300 above, whenusing the clinical effect analysis screen 500, as long as a therapeuticeffect is perceived, the user preferably incrementally increases theintensity level of the stimulation energy via the intensity leveladjustment control 302 until the side-effect is intolerable, so that theside-effect can be fully determined by the CP 18.

The user may enter the score into the therapeutic score box 506 a as arelative improvement in a symptom, with 0% representing no improvementin the symptom, and 100% representing total elimination of the symptomas if there were no disease state. In contrast to the clinical effectanalysis screen 300 of FIG. 12 where a bar map 308 is generated for eachof the disorders, the clinical effect analysis screen 500 generates acomposite score from the individual scores corresponding to therespective disorders, so that one bar map is generated for the multipledisorders. For example, at a particular intensity level for a particularelectrode, if a score of 10% is entered for Parkinson's Disease, and ascore of 40% is entered for Essential Tremor, the CP 18 will determinethe composite score to be 25%. In an optional embodiment, the disordersmay be weighted, such that the scores for one disorder affect thecomposite score more than the scores for another disorder. For example,if Parkinson's Disease is weighted twice as much as Essential Tremor,the composite score in the exemplary case may be 35% instead of 25%. Ifmultiple side-effects are perceived by the patient, the user may enterthe worst-case score into the side-effect score box 506 b. For example,if two side-effects are experienced by the patient (e.g., nausea andslurred speech), and one side-effect is really bad, whereas the otherside-effect is minimal, the score for the one side-effect can be enteredinto the side-effect score box 506 b, whereas the score for the otherside-effect can be ignored. In an alternative embodiment, a generalwellness score box (not shown) can be used to enter a wellness scorethat takes into account the therapeutic effect and side-effect resultingfrom the electrical stimulation energy at each incremental intensitylevel.

In this embodiment, the CP 18 graphically generates and displays thisinformation in the form of bar map 508 for the electrodes E1-E8. The barmap 508 includes a sets of vertical bars 510, each set being displayedon a line “Th” next to the electrode that is currently selected fortesting. Each of the vertical bars 510 indicates the relative level (inthis case, a score) of the therapeutic effect at each incrementalintensity level for each of the electrodes E1-E8. The height of eachvertical bar 510 is proportional to the score that it indicates, suchthat as the score increases, the height of the corresponding verticalbar 510 increases. In the case where there is no therapeutic effect atan incremental intensity level, no bar is generated and displayed.

The bar map 508 also includes horizontal bars 512, each of which isdisplayed on a line “SE” next to the electrode that is currentlyselected for testing. Each of the horizontal bars 512 is graduated withdifferent shades to indicate the relative level (in this case, a score)of the side-effect at the incremental intensity levels for each of theelectrodes E1-E8. The darkness of the shades in each of the horizontalbars 510 is proportion to the score that it indicates, such that as thescore increases, the shade becomes darker. Thus, the beginning of wherethe shading in the horizontal bar 510 appears indicates the beginning ofthe side-effect (i.e., when the side-effect is initially perceived),which increases in darkness, with a black shading indicating that theside-effect has become intolerable. In this case where there is noside-effect at an incremental intensity level, no shade is displayed. Inan optional embodiment, the bar map 508 further includes an intolerableside-effect indicator (not shown) that can be generated and displayed atthe respective incremental intensity level that it is perceived. To thisend, the clinical effect analysis screen 500 may include a triggerbutton (not shown) that can be actuated by the user to indicate when aside-effect is intolerable to the patient.

Notably, because the pulse width and pulse rate of stimulation energyused to treat different disorders will differ from each other, the userwill typically test all of the electrodes for one disorder beforetesting all of the electrodes for another disorder. For example, aftertesting all of the relevant electrodes and entering the clinicalinformation for one disorder, the user can return to the therapyselection screen 200, select another disorder via the disorder boxes202, and then go to the clinical effects analysis screen 500 to test therelevant electrodes and enter the clinical information for the otherdisorder.

In the example illustrated in FIG. 16, and with further reference toFIG. 11, no vertical bar 510 and a moderate intensity shading for thehorizontal bar 512 is displayed adjacent electrode E1, indicating to theuser that electrode E1 highly influences a side-effect region withoutinfluencing a therapeutic effect at all, which corresponds to electrodeE1 being partially contained in the first side-effect region SE1. Thehighest score vertical bar 510 displayed adjacent electrode E2 is 40%;however, the side-effect is initially perceived before that vertical bar510, indicating to the user that electrode E2 somewhat influences atherapeutic effect and a side-effect, which corresponds to electrode E2being between the first therapy region TH1 and the first side-effectregion SE1. The highest score vertical bar 510 displayed adjacentelectrode E3 is 80%, with the side-effect being initially perceivedafter this vertical bar 510, indicating that electrode E3 highlyinfluences a therapeutic effect, which corresponds to electrode E3 beingfully within the first therapy region TH1. The highest score verticalbar 510 displayed adjacent electrode E4 is 100%, with the side-effectnever being perceived at all, indicating that electrode E4 highlyinfluences a therapeutic effect, which corresponds to electrode E4 beingin the center of the first therapy region TH1. The highest scorevertical bar 510 displayed adjacent electrode E5 is 40%; however, theside-effect is initially perceived before that vertical bar 510,indicating to the user that electrode E5 somewhat influences atherapeutic effect and a side-effect, which corresponds with electrodeE5 being partially contained in the first and second therapy regionsTH1, TH2, and near the second side-effect region SE2. No vertical bar510 and a moderate intensity shading for the horizontal bar 512 isdisplayed adjacent electrode E6, indicating to the user that electrodeE6 highly influences a side-effect region without influencing atherapeutic effect at all, which corresponds to electrode E6 beingcontained in the second side-effect region SE1. The question marksadjacent electrodes E7 and E8 have not been tested, presumably by choiceof the user based on the fact that the therapeutic effect diminished atelectrode E6.

In an optional embodiment, the bar map 508 is used by the CP 18 todefine and display a target tissue region for stimulation. Inparticular, as shown in FIG. 17, the CP 18 may automatically define aline 518 that connects relevant points 520 within the bar map 508. Inthe illustrated embodiment, each of the points 520 are located in thegap between the incremental intensity level corresponding to the highestscore vertical bar 510 and the incremental intensity level at which aside-effect is initially perceived for the respective electrode. The CP18 may then smooth the line 518 and revolve it around a vertical axis522 defined by the electrodes to create a bi-laterally symmetricaltarget tissue region 524, as shown in FIG. 18, which can be displayed tothe user to aid in programming the IPG 14. In the case, where athree-dimensional target tissue region is generated and displayed, theline 518 is revolved around the vertical axis of the electrodes todefine a three-dimensional volume.

In alternative embodiments, the connecting points 520 may be located atother locations in the bar map 508, such as, e.g., at the incrementalintensity levels corresponding to the highest score vertical bars 510,at a point halfway between the incremental intensity level correspondingto the highest score vertical bar 510 and the incremental intensitylevel at which an intolerable side-effect is perceived for therespective electrode. In the same manner as discussed above with respectto FIGS. 13 and 14, a range of differently aggressive target tissueregions 524 may be created with the different lines 518.

Referring to FIG. 19, a clinical effect analysis screen 600 is similarto the clinical effect analysis screen 300 described above, with theexception that the CP 18 generates a volume map 608 instead of a bar map308. The clinical effect analysis screen 600 also includes a pluralityof therapeutic effect trigger buttons (in this case, two therapeutictrigger buttons 606 a, 606 b) that can be actuated when the patientrespectively experiences a plurality of different therapeutic effects,and a plurality of side-effect trigger buttons (in this case, twoside-effect trigger buttons 606 c, 606 d) that can be actuated when thepatient respectively experiences a plurality of different side-effects.For example, if the patient experiences one therapeutic effect, the usermay actuate the first therapeutic trigger button 606 a, and if thepatient experiences another different therapeutic effect, the user mayactuate the other therapeutic trigger button 606 b. Likewise, if thepatient experiences one side-effect, the user may actuate the firstside-effect trigger button 606 c, and if the patient experiences anotherdifferent side-effect, the user may actuate the other side-effecttrigger button 606 d.

The different therapeutic effects (and likewise, the differentside-effects) can be concurrently experienced by the patient or may beexperienced by the patient during different times. In the same mannerdiscussed above with respect to the clinical effect analysis screen 300,the CP 18 quantifies the influence of each electrode 26 on thetherapeutic effect by determining the range of incremental intensitylevels at which a metric of each of the therapeutic effects occurs basedon verbal feedback from the patient, and further determining theincremental intensity level at which a metric of each of theside-effects initially occurs. However, the CP 18 further quantifies theinfluence of each electrode 26 on the clinical effects by determiningthe electrodes that most influence the therapeutic effects and theside-effects, and generates the volume map 608 based on this determinedclinical information.

The volume map 608 includes one or more target tissue regions (in thiscase, two target regions T1, T2) displayed adjacent the electrodes thatare determined to most influence the therapeutic effects, and one ormore non-target tissue regions (in this case, two non-target tissueregions N1, N2) displaced adjacent the electrodes that are determined tomost influence the side-effects. In the illustrated embodiment, theregions are illustrates as being two-dimensional, although in otherembodiments, the regions can be illustrated as being three-dimensionalin nature. The portion of the map 608 that is hatched representsunexplored area, thereby allowing the user to readily determine theportion of the tissue has been explored and the portion of the tissuethat has been explored (i.e., either designated as target tissue ornon-target tissue). The different target regions T1, T2 and non-targettissue regions N1, N2 may be coded with different colors to enable theuser to more easily distinguish the different target regions from eachother and the target regions from the non-target regions. For example,the border of the first target tissue region T1 may be colored green,the border of the second target tissue region T2 maybe colored purple,and the borders of the non-target tissue regions N1, N2 may be coloredorange. The target tissue regions T1, T2 and non-target tissue regionsN1, N2 may also be filled in with different colors.

In one embodiment, the CP 18 estimates the size and shape of the targettissue region based on the highest incremental intensity level oftherapeutic effects for each electrode. The CP 18 estimates the size andshape of the non-target tissue regions as being closely surrounding theelectrode determined to influence the side-effects corresponding to thenon-target tissue regions. Notably, the exact boundaries of the volumeor region of tissue influenced by the electrodes may not be initiallyknown (only that the volume or region of tissue is close by). However,the boundaries of the volume or region of tissue influenced by theelectrodes may be estimated using an atlas of known target andnon-target tissue regions or may be deduced as clinical information iscollected by the CP 18 in subsequent stimulation scenario steps. Inanother embodiment, the CP 18 estimates either an electric field or aregion of tissue activation at the highest incremental intensity levelat which the therapeutic effects occur for each electrode, anddetermines the size and shape of the target tissue regions based on thisinformation. Logical operators may be used to estimate each influencingelectrode's contribution on the relevant target tissue region.

For example, when electrode E1 is activated at an amplitude high enoughto evoke a side-effect, the stimulated region could be modeled and onecould deduce that somewhere on the outer boundary of the stimulationfield model the excitation has resulted in a side-effect, but not knowexactly which part of the stimulation field model boundary isresponsible. If electrode E2 is then activated, it may be that at someamplitude where a side effect is not yet reached, a new stimulationfield model could be generated that overlaps the stimulation field modelgenerated during the test with electrode E1 (which evoked the sideeffect). It can now be deduced that the part of the boundary of thestimulation field model from the test of electrode E1 (at side effectthreshold) that is overlapping with the stimulation field model with thetest of electrode E2 (no side effect) is not responsible for the sideeffect, and this information can be graphically provided to the user(e.g., change in color, etc. of some part of the clinical effects map).Note that other logical deductions can be performed as more informationis gathered, and these deductions can be graphically conveyed to theuser.

For example, as shown in FIG. 19 and with further reference to FIG. 11,a relatively small non-target tissue region N1 surrounds electrode E1,indicating to the user that electrode E1 influences a side-effect, whichcorresponds to electrode E1 being partially contained in the firstside-effect region SE1. A relatively large target tissue region T1surrounds electrodes E2-E5, indicating to the user that electrodes E2-E5influence a therapeutic effect, with the width of the target tissueregion T1 being greatest at electrode E4 and tapering down at electrodesE2, E3, and E5, indicating that electrode E4 highly influences thetherapeutic effect. This corresponds with electrode E2 being adjacentthe first therapy region TH1, electrode E3 being fully within the firsttherapy region TH1, electrode E4 being in the center of the firsttherapy region TH1, and electrode E5 being partially contained in thefirst therapy region TH1. A relatively small target tissue region T2surrounds electrodes E4-E5, indicating to the user that electrodes E4and E5 influence another therapeutic effect, which corresponds toelectrode E4 being fully contained within the second therapy region TH2and electrode E5 being partially contained in the second therapy regionTH2. A long scalloped non-target region surrounds electrodes E6-E8,indicating to the user that electrodes E6-E8 influence anotherside-effect region, which corresponds to electrodes E6-E8 beingcontained within the second side-effect region SE2.

Referring to FIGS. 20a-20d , the CP 18 may generate and display thevolume map 608 in a progressive manner as clinical information isentered by the user. For example, after clinical information is enteredfor electrode E1, the CP 18 may generate and display the firstnon-target tissue region N1 around electrode E1 (FIG. 20a ). Afterclinical information is entered for electrode E2, the CP 18 may generateand display the first target tissue region T1 around electrode E2 (FIG.20b ). As clinical information is gathered for electrodes E3-E5, thefirst target tissue region T1 grows larger, and the second target tissueregion T2 is added (FIG. 20c ). As clinical information is gathered forelectrodes E6-E8, the second non-target tissue region N2 is added aroundthese electrodes (FIG. 20d ).

In an optional embodiment, instead of having the user manually test eachelectrode for clinical effects in a methodical manner, the CP 18 maysuggest electrodes or electrode combinations that can be subsequentlytested by the user to obtain the best clinical information. For example,referring to FIG. 30, an optimization algorithm can be used to estimatethe best electrode configuration that provides the best therapeuticstimulation. The user may enter the position of the neurostimulationlead or leads into the CP 18 (e.g., based on atlas, stereotacticcoordinates, user estimate, etc.), and the clinical effects datacollected during programming, and the CP 18 may output the optimalelectrode configuration, and optionally, the optimum pulse amplitude,pulse width and pulse rate. The optimization algorithm may be anoptimization cost function designed with the objective of providing the“best guess” optimal electrode configuration and/or other stimulationparameters. Alternatively, the cost function could be designed to revealall or a specific part of the clinical effects “map” or explore part ofthe anatomy. This latter objective could have the purpose of obtaininginformation that will subsequently inform an estimate of optimaltherapeutic stimulation (e.g., the explored data may contribute torefining the lead-to-therapeutic region relationship).

Referring back to FIG. 9, the CP 18 is capable of modifying theanatomical regions of interest (namely, the therapy tissue region 124and the side-effect tissue region 126), as obtained from the atlas, tobe more patient-specific and to correct any mis-registration between theanatomical regions of interest and the neurostimulation lead 12. This isaccomplished by conveying electrical stimulation into the tissue of thepatient via selected electrodes, thereby creating one or more clinicaleffects, determining an influence of the specified electrodes on theclinical effects, and modifying the anatomical regions of interest(e.g., by spatially translating the anatomical regions of interestrelative to the graphical electrode representation 26′ or by changingthe shape of the anatomical regions of interest) based on the determinedinfluence of the specified electrodes on the clinical effects.

In one embodiment shown in FIG. 21, an atlas modification screen 700includes the previously described intensity level adjustment control302, electrode selection control 304, and clinical information entrybuttons 306 that can be actuated in the same manner described above withrespect to the clinical effect analysis screen 300 to adjust theintensity of the electrical stimulation energy and select the electrodevia which the electrical stimulation energy will be conveyed, and toenter clinical information as a result of such conveyed electricalstimulation energy, and in particular, to indicate to the CP 18 theintensity level at which the patient experiences a therapeutic effect orside-effect. The atlas modification screen 700 also includes thegraphical representation of the neurostimulation lead 12′ and thecorresponding electrodes 26′, as well as the registered anatomicalregions of interest, and in this example, the therapy tissue region 124and side-effect tissue region 126. Based on clinical information enteredby the user in response to conveying electrical stimulation energy viaselected ones of the electrodes, the CP 18 may heuristically determinethe manner in which the anatomical regions of interest should bemodified.

In one embodiment, the CP 18 may determine the proximity between adisplayed anatomical region of interest and a specified electrode in thegraphical electrode representation 26′. The determined proximity maysimply be a rough estimate, such as, e.g., a relatively large proximityor a relatively small proximity. For example, as shown in FIG. 22a , theproximity between the displayed therapy tissue region 124 and electrodeE3 may be determined to be relatively large. In another example, asshown in FIG. 22b , the proximity between the displayed therapy tissueregion 124 and electrode E3 may be determined to be relatively small.

The CP 18 may then imply an actual proximity between the displayedanatomical region of interest and the specified electrode based on thedetermined influence of the specified electrode on the clinical effects.For example, electrode E3 can be selected for conveying the electricalstimulation energy via the electrode selection control 304, and theintensity of the conveyed electrical stimulation energy can beincrementally increased via the intensity adjustment control 302 until atherapeutic effect is perceived by the patient. If the intensity levelat which the therapeutic effect is initially perceived is relativelylow, the CP 18 may determine the actual proximity between the therapytissue region 124 and electrode E3 to be relatively small, and if theintensity level at which the therapeutic effect is initially perceivedis relatively high, the CP 18 may determine the actual proximity betweenthe therapy tissue region 124 and electrode E3 to be relatively large.

The CP 18 may then spatially translate the displayed anatomical regionof interest relative to the specified electrode in the graphicalelectrode representation 26′ to better match the displayed proximity tothe actual proximity. This can be accomplished by moving either thedisplayed anatomical region of interest within the screen 700 or movingthe graphical electrode representation 26′ within the screen 700, suchthat there is a relative displacement between the displayed anatomicalregion of interest and the graphical electrode representation 26′.

For example, in the case where the proximity between the displayedtherapy tissue region 124 and electrode E3 is relatively large, as shownin FIG. 22a , the CP 18 may displace the displayed therapy tissue region124 toward electrode E3 (as shown in phantom) if the actual proximitybetween the therapy tissue region 124 and electrode E3 is determined tobe relatively small. This is because the initial perception of atherapeutic effect at a relatively low intensity level, which indicatesthat the actual proximity between the therapy tissue region 124 andelectrode E3 is relatively small, contradicts the displayed proximitybetween the therapy tissue region 124 and electrode E3 as beingrelatively large, and therefore, the displayed therapy tissue region 124should be moved toward electrode E3 to better match the actual proximitybetween the therapy tissue region 124 and electrode E3. Assuming thatthe actual proximity between the therapy tissue region 124 and theside-effect tissue region 126 are the same, the displayed side-effecttissue region 126 may also be spatially translated away from electrodeE3 in the same distance in the same direction that the displayed therapytissue region 124 is spatially translated away from electrode E3 (asshown in phantom) in order to maintain the spatial relationship betweenthe therapy tissue region 124 and the side-effect tissue region 126.

As another example, in the case where the proximity between thedisplayed therapy tissue region 124 and electrode E3 is relativelysmall, as shown in FIG. 22b , the CP 18 may displace the displayedtherapy tissue region 124 away from electrode E3 (as shown in phantom)if the actual proximity between the therapy tissue region 124 andelectrode E3 is determined to be relatively large. This is because theinitial perception of a therapeutic effect at a relatively highintensity level, which indicates that the actual proximity between thetherapy tissue region 124 and electrode E3 is relatively large,contradicts the displayed proximity between the therapy tissue region124 and electrode E3 as being relatively small, and therefore, thedisplayed therapy tissue region 124 should be moved away from electrodeE3 to better match the actual proximity between the therapy tissueregion 124 and electrode E3. Assuming that the actual proximity betweenthe therapy tissue region 124 and the side-effect tissue region 126 arethe same, the displayed side-effect tissue region 126 may also bespatially translated away from electrode E3 the same direction in thesame direction that the displayed therapy tissue region 124 is spatiallytranslated away from electrode E3 (as shown in phantom) in order tomaintain the spatial relationship between the therapy tissue region 124and the side-effect tissue region 126.

The CP 18 may displace the displayed side-effect tissue region 126relative to electrode E3 or any other specified electrode using the sametechnique described above to displace the therapeutic tissue region 126relative to electrode E3.

In another embodiment, the CP 18 may determine a relative influence of aspecified electrode on a therapeutic effect and a side-effect, andspatially translate or rotate the displayed anatomical region ofinterest relative to the specified electrode in the graphical electroderepresentation 26′ based on the determined relative influence of thespecified electrode on the therapeutic effect and the side-effect.

As one example, in the case where the proximity between the displayedtherapy tissue region 124 and electrode E3 is relatively large, and theproximity between the displayed side-effect region 124 and electrode E3is relatively small, as shown in FIG. 23a , electrode E3 can be selectedfor conveying the electrical stimulation energy via the electrodeselection control 304, and the intensity of the conveyed electricalstimulation energy can be incrementally increased via the intensityadjustment control 302 until a clinical effect is perceived by thepatient. If a therapeutic effect is entered by the user as the firstclinical effect that is perceived by the patient, the CP 18 mayspatially translate the displayed therapy tissue region 124 towardelectrode E3, and spatially translate the displayed side-effect tissueregion 126 away from electrode E3 (as shown in phantom). That is,because the initial perception of a therapeutic effect contradicts thedisplay of electrode E3 closer to the side-effect tissue region 126 thanthe therapy tissue region 124, it is determined that electrode E3 isactually closer to the therapy tissue region 124 than the side-effecttissue region 126, and therefore, the displayed therapy tissue region124 should be moved toward electrode E3, and the displayed side-effecttissue region 126 should be moved away from electrode E3.

As one example, in the case where the proximity between the displayedtherapy tissue region 124 and electrode E3 is relatively small, and theproximity between the displayed side-effect region 124 and electrode E3is relatively large, as shown in FIG. 23b , electrode E3 can be selectedfor conveying the electrical stimulation energy via the electrodeselection control 304, and the intensity of the conveyed electricalstimulation energy can be incrementally increased via the intensityadjustment control 302 until a clinical effect is perceived by thepatient. If a side-effect is entered by the user as the first clinicaleffect that is perceived by the patient, the CP 18 may spatiallytranslate the displayed therapy tissue region 124 away from electrode E3and spatially translate the displayed side-effect tissue region 126toward electrode E3 (as shown in phantom). That is, because the initialperception of a side-effect contradicts the display of electrode E3closer to the therapy tissue region 124 than the side-effect tissueregion 126, it is determined that electrode E3 is actually closer to theside-effect region 126 than the therapy tissue region 124, andtherefore, the displayed therapy tissue region 124 should be moved awayfrom electrode E3, and the displayed side-effect tissue region 126should be moved toward electrode E3.

In another embodiment, two different electrodes are selected via theelectrode selection control 304. The electrodes are selected, such thatone of the electrodes is further away from the displayed anatomicalregion of interest than the other electrode in the graphical electroderepresentation 26′. For example, electrodes E2 and E4 can be selected,with electrode E2 being further away than electrode E4 from thedisplayed therapy tissue region 124, as shown in FIG. 24. The intensityof the electrical stimulation conveyed via the two different electrodesis adjusted via the intensity level adjustment control 302, such thatthe CP 18 may quantify an influence of each of electrodes E2 and E4 on atherapeutic effect.

For example, the intensity of the electrical stimulation energy conveyedvia electrode E2 can be incrementally increased via the intensityadjustment control 302 until a therapeutic effect is perceived by thepatient, and then the intensity of the electrical stimulation energyconveyed via electrode E4 can be incrementally increased via theintensity adjustment control 302 until a therapeutic effect is perceivedby the patient. If the intensity level at which the therapeutic effectis initially perceived for electrode E2 is lower than the intensitylevel at which the therapeutic effect is initially perceived forelectrode E4 (i.e., electrode E2 has a higher influence than electrodeE4 on the therapeutic effect), the CP 18 spatially translate thedisplayed therapeutic tissue region 124 away from electrode E4 andtowards electrodes E2 in the graphical electrode representation 26′.That is, because the intensity levels at which the therapeutic effectfor electrodes E2 and E4 contradict the display of electrode E2 beingfurther than electrode E4 from the therapy tissue region 124, it isdetermined that electrode E2 is actually closer than electrode E4 to thetherapy tissue region 124, and therefore, the displayed therapy tissueregion 124 should be toward electrode E2 and away from electrode E4.

In still another embodiment, the CP 18 may change the shape of, warp, ormorph an anatomical region of interest based on the clinical informationentered via the clinical effect analysis screens 300, 400, 500, or 600discussed above. For example, electrical stimulation energy may beserially conveyed via different ones of the electrodes E1-E8, and foreach electrode, the intensity level of the conveyed electricalstimulation energy may be incrementally increased. The CP 18 mayquantify the therapeutic effect by determining the highest intensitylevel at which a metric of the therapeutic effect occurs prior to aninitial occurrence of a metric of a side-effect, and change the shape ofthe therapy tissue region based on the determined highest intensitylevels for the different electrodes. That is, the higher the intensitylevel, the larger the therapy region at the respective electrode shouldbe, and the CP 18 will accordingly modify the shape of the displayedtherapy tissue region 124.

In one example, the additional clinical effects information could beused by an algorithm (or manually by the user) to refine an atlas and/orthe atlas and lead relationship such that a new atlas-to-leadrelationship is more consistent with the clinical effects informationthat has been gathered, based on knowledge or expectations aboutstimulation of certain anatomical regions resulting in certain knownclinical or physiological effects. If algorithm based, the algorithm islikely to include stimulation field models and their overlap orproximity to certain anatomical structures. Note that to get robustcongruence of clinical data and the atlas-to-lead relationship, thewarping or the morphing of the atlas may require more than translationsand rotations, but perhaps also stretching and affine transformations,spline-type transformations, non-uniform rational B-splinetransformations, and alternatives or the like.

Although We need to include rotating, warping, morphing, or generallyreshaping. One imagines an algorithm that takes into account the imagingdata and the clinical effects data, to get an overall best match

Referring to FIG. 25, the CP 18 is capable of allowing a user to moreeasily match an electric field corresponding to a set of stimulationparameters to a desired electric field via an electric field selectionscreen 800, which allows the user to select for an electric field one ofa plurality of different pre-defined shapes stored within memory 82, anddefine a location of the electric field relative to the graphicalelectrode representation 26′. To this end, the programming screen 800includes the intensity level adjustment control 302 that can be actuatedin the same manner described above to adjust the intensity of theconveyed electrical stimulation energy. The programming screen 800 alsoincludes a graphical representation of the neurostimulation lead 12′ andthe corresponding electrodes 26′, as well as anatomical regions ofinterest, and in this example, two therapy tissue regions 124 a and 124b, set off from the graphical representation of the neurostimulationlead 12′ and corresponding electrodes 26′.

Significantly, the electric field selection screen 800 includes anelectric field selection control 802 that allows the user to selectpre-defined electric field shapes that can be located relative to thegraphical electrode representation 26′. In particular, the electricfield selection control 802 displays various graphical shapes 804 a-804c that can be dragged and dropped onto the graphical electroderepresentation 26′. In the illustrated embodiment, the first graphicalshape 804 a is an upside down pear shape (which emulates a bipolarelectric field with the cathode at the top), the second graphical shape804 b is a right-side up pear shape (which emulates a bipolar electricfield with the cathode at the bottom), and the third graphical shape 804a is a sphere (which emulates a monopolar electric field). Inalternative embodiment, other types of shapes, such as a triangle oroval, may be provided.

Preferably, the user compares the pre-defined graphical shapes 804 tothe therapeutic tissue region 124, and selects the graphical shape 804that best matches the shape of the therapeutic region 124. The userpreferably locates the selected shape 804 to match the location of thetherapeutic tissue region 124 relative to the graphical electroderepresentation 26′. In an optional embodiment, the CP 18 willautomatically locate the user-selected graphical shape 804 to match thelocation of the therapeutic tissue region 124. Notably, as shown in FIG.26, multiple graphical shapes 804 can be selected, dragged, and droppedonto the graphical electrode representation 26′. The selected graphicalshapes 804 may either be different from each other, as illustrated inFIG. 26, or may be identical to each other. In either case, the CP 18will prevent the multiple graphical shapes 804 from intersecting eachother if the user attempts to move one of the selected graphical shapes804 into another selected graphical shape 804.

The manner in which a graphical shape 804 is selected, dragged, anddropped will depend on the nature of the user interface. For example, ifthe display screen 76 is conventional, a virtual pointing device (e.g.,cursor controlled by the mouse 72, joy stick, trackball, etc.) can beused to select, drag, and drop the graphical shape 804 onto thegraphical electrode representation 26′. If the display screen 76 is adigitizer screen, a physical pointing device (e.g., a stylus or finger)can be used to select, drag, and drop the graphical shape 804 onto thegraphical electrode representation 26′.

In the preferred embodiment, the CP 18 determines the combination ofelectrodes that best emulates the selected shape and defined location ofthe electric field. In the illustrated embodiment, the electrodecombination that is determined to best match the electric field is afractionalized electrode combination. The CP 18 may dynamicallydetermine the fractionalized electrode combination as the graphicalshape 804 is moved relative to the graphical electrode representation26′. For example, as the graphical shape 804 a is moved along the lengthof the graphical electrode representation 26′ (as shown by arrows), asshown in FIG. 27, the CP 18 may compute the fractionalized electrodecombination corresponding to each of the locations of the graphicalshape 804 a relative to the electrodes. In an optional embodiment, oncethe graphical shape 804 is dragged and dropped onto the graphicalelectrode representation 26′, one side of the graphical shape 804 may bemoved (e.g., in the direction of the arrow) in order to expand orcontract the graphical shape 804 in one direction, as shown in FIG. 28.Furthermore, the size of the selected graphical shape 804 may be changed(either making it larger or smaller) by actuating the intensity leveladjustment control 302 (i.e., increasing the intensity increases thesize of the selected graphical shape 804, and decreasing the intensitydecreases the size of the selected graphical shape 804).

The CP 18 may alternatively automatically determine the combination ofelectrodes that best emulates the selected shape and defined location ofthe electric field using any one of a variety of known techniques. Forexample, the CP 18 may theoretically overlay a grid of spatialobservation points over the electric field, with each point assuming anelectric field magnitude value. It can be assumed that the magnitude atthe center of the electric field is highest, which exponentially tapersoff towards the edges of the electric field.

Linearly independent constituent sources are then selected at thelocations of electrodes E1-E8. Preferably, the constituent currentsources are linearly independents. In the illustrated embodiment,bipoles are selected as constituent sources, because they are simple,and lend themselves well to conservation of current (i.e., if allconstituent sources have conserved current (net zero), then any linearcombination of them will also have conserved current). For example, afirst constituent current source can be defined at the locations ofelectrodes E1 and E2 as −100% and +100%, respectively; a secondconstituent current source can be defined at the locations of electrodesE2 and E3 as −100% and +100%, respectively; a third constituent currentsource can be defined at the locations of electrodes E3 and E4 as −100%and +100%, respectively; and so on.

Once the constituent sources are selected, the CP 18 determines therelative strengths of the constituent current sources that, whencombined, result in estimated electric field potential values at thespatial observation points that best matches the desired field potentialvalues at the spatial observation points. In particular, the CP 18models the constituent current sources (e.g., using analytical and/ornumerical models) and estimates the field potential values per unitcurrent (V/mA) generated by each of the constituent current sources atthe spatial observation points, and generating an m×n transfer matrixfrom the estimated field potential values per unit current, with mequaling the number of spatial observation points and n equaling thenumber of constituent sources. The relative strengths of the constituentcurrent sources are determined using an optimization function thatincludes the transfer matrix A and the desired field potential values.This technique is described in further detail in U.S. patent applicationSer. No. 12/938,282, entitled “System and Method for Mapping ArbitraryElectric Fields to Pre-Existing Lead Electrodes,” which is expresslyincorporated herein by reference.

The CP 18 may instruct the IPG 14 to convey electrical stimulationenergy to the fractionalized electrode combination determined to emulatethe electric field, thereby creating one or more clinical effects. Ifthe user selects different ones of the graphical shapes 804 and/ordifferent locations for a selected graphical shape 804, the IPG 14 mayinstruct the IPG 14 to convey electrical stimulation energy for each ofthe fractionalized electrode combinations determined to emulate thedifferent electrical fields corresponding to the different graphicalshapes and/or different locations for the graphical shapes, therebycreating a clinical effect for each of the determined fractionalizedelectrode combinations. The user may enter a score for each of thefractionalized electrode combinations, in which case, the CP 18 maysubsequently present the top-rated fractionalized electrode combinationsto the user for therapy.

In another embodiment, the CP 18 may generate a plurality of differentelectric fields that best match a target tissue region (which maycorrespond to the target tissue region 324 generated in response toclinical information entered by the user or may be imported into the CP18). The CP 18 can also determine the fractionalized electrodecombinations that best emulate the different electric fields, e.g., inthe manner described above. The CP 18 may present the best matchingelectric fields to the user (e.g., the top three matching electricfields), as shown in a program selection screen 900 shown in FIG. 29.

In particular, the program selection screen 900 may display threegraphical shapes 902 corresponding to the shape of the there bestmatching electric fields, and a percentage coverage 904 for eachelectric field (i.e., the percentage of the area of the correspondingtarget tissue region covered by the respective electric field). Theprogram selection screen 900 further includes selection buttons 906 thatcan be clicked by the user to prompt the CP 18 to instruct the IPG 14 toconvey electrical stimulation energy in accordance with thefractionalized electrode combination corresponding to the selectedelectric field. The user may be prompted to incrementally increase theintensity of the conveyed electrical stimulation energy (e.g., via anintensity level adjustment control) until the therapy is optimum.

There may be instances where side-effects and therapy overlap. Hence, itmay be useful to convey a constant amount of electrical stimulationenergy, while varying the pulse amplitude and pulse width (i.e.,inversely varying the pulse amplitude and pulse width, such that if thepulse amplitude is increased, the pulse width is decreased, and if thepulse amplitude is decreased, the pulse width is increased). Forexample, if the conveyed electrical stimulation energy has a pulse widthof 60 μs and a pulse amplitude of 2 mA, the pulse width can be slowlydecreased to 30 μs while the pulse amplitude is increased to slowlyincreased to 4 mA (stopping at various points to evaluate thetherapy/side-effects). Similarly, the pulse width can be slowlyincreased to 120 μs from 60 μs while the pulse amplitude is decreasedfrom 4 mA to 1 mA.

Once optimum therapy is achieved, the user may enter a score 908 andsave the fractionalized electrode combination along with the adjustedintensity as a program. In the illustrated embodiment, this score 908 isa wellness that takes into account both therapy and side-effects. Thedifferent programs can be designated as either very conservative (e.g.,minimal or moderate therapy with very little or no side-effects) thatcan be used during a period of time when maximum therapy is not needed(e.g., during sleep); very aggressive (e.g., maximum therapy withsubstantial side-effects) that can be used during a period of time whenmaximum therapy is desired (e.g., during performance of intricatephysical tasks); or moderate (moderate therapy with littleside-effects). The CP 18 may have a control for selecting the programbased on how conservative or aggressive it is.

Although the foregoing techniques have been described as beingimplemented in the CP 18, it should be noted that this technique may bealternatively or additionally implemented in the RC 16. Althoughparticular embodiments of the present inventions have been shown anddescribed, it will be understood that it is not intended to limit thepresent inventions to the preferred embodiments, and it will be obviousto those skilled in the art that various changes and modifications maybe made without departing from the spirit and scope of the presentinventions. Thus, the present inventions are intended to coveralternatives, modifications, and equivalents, which may be includedwithin the spirit and scope of the present inventions as defined by theclaims.

What is claimed is:
 1. An external programmer for use with a neurostimulator, comprising: output circuitry configured to communicate with the neurostimulator; control circuitry configured to instruct the neurostimulator via the output circuitry to convey electrical stimulation energy into tissue of a patient via different combinations of electrodes implanted within the patient, thereby creating one or more clinical effects for each of the different electrode combinations; and processing circuitry configured to determine an influence of each of the different electrode combinations on the one or more clinical effects, and generate a graphical indication of the one or more clinical effects based on the influence of different electrode combinations; wherein the control circuitry is further configured to instruct a display device to display an electrode selection control configured to allow user selection of the different electrode combinations, and instruct display of the graphical indication of the one or more clinical effects based upon electrical stimulation energy conveyed into the tissue of the patient via the neurostimulator adjacent a graphical rendering of the electrodes such that the user can view a data map that quantifies an extent to which each of the different electrode combinations influences the one or more clinical effects, and modify display of the graphical indication of the one or more clinical effects by at least one of spatially translating the graphical indication of the one or more clinical effects and changing a shape of the graphical indication relative to the graphical rendering of the electrodes based on the determined influence of the user selection of different electrode combinations.
 2. The external programmer of claim 1, further comprising a user interface configured to allow a user to enter clinical information on the one or more clinical effects for the each different electrode combination, wherein the processing circuitry is configured to determine the influence of the each different electrode combination on the one or more clinical effects based on the clinical information entered by the user, wherein the data map is a bar map representing the extent to which each of the different electrode combinations influences the one or more clinical effects.
 3. The external programmer of claim 1, further comprising monitoring circuitry configured to monitor the one or more clinical effects for the each different electrode combination, wherein the processing circuitry is configured to determine the influence of the each different electrode combination on the one or more clinical effects based on the monitored one or more clinical effects.
 4. The external programmer of claim 1, wherein each of the electrode combinations has only one electrode.
 5. The external programmer of claim 1, wherein at least one of the electrode combinations comprises a fractionalized electrode combination.
 6. The external programmer of claim 1, wherein the one or more clinical effects comprises a therapeutic effect.
 7. The external programmer of claim 1, wherein the one or more clinical effects comprises a side-effect.
 8. The external programmer of claim 1, wherein the control circuitry is further configured to in struct the neurostimulator via the output circuitry to incrementally increase an intensity level of the conveyed electrical stimulation energy for each of the different electrode combinations; and wherein the processing circuitry is configured for determining the influence of the each different electrode combination on the one or more clinical effects for each intensity level.
 9. The external programmer of claim 8, wherein the one or more clinical effects comprises one or more therapeutic effects, and the processing circuitry is configured to determine the influence of the each different electrode combination on the one or more therapeutic effects by determining a range of incremental intensity levels at which a metric of the one or more therapeutic effects occurs.
 10. The external programmer of claim 9, wherein the one or more clinical effects further comprises one or more side-effects, and the processing circuitry is further configured to determine the influence of the each different electrode combination on the one or more side-effects by determining an incremental intensity level at which a metric of the one or more side-effects initially occurs.
 11. The external programmer of claim 10, wherein the processing circuitry is further configured to determine the influence of the each different electrode combination on the one or more therapeutic effects by determining a highest intensity level at which the one or more therapeutic effect metrics occur prior to the initial occurrence of one or more side-effect metrics.
 12. The external programmer of claim 11, wherein the graphical indication of the one or more clinical effects comprises a bar map having a plurality of bars, each of which indicates for the each different electrode combination the highest intensity level at which the one or more therapeutic effect metrics occur prior to the initial occurrence of the one or more side-effect metrics.
 13. The external programmer of claim 12, wherein the therapeutic effect metric is a perception threshold of the one or more therapeutic effects, and the side-effect metric is one of a perception threshold of the one or more side-effects, an uncomfortable threshold of the one or more side-effects, and an intolerable threshold of the one or more side-effects.
 14. The external programmer of claim 9, wherein the therapeutic effect metric is a relative level of the one or more therapeutic effects.
 15. The external programmer of claim 14, wherein the one or more therapeutic effects comprises a plurality of therapeutic effects, and the relative level is a composite score as a function of individual scores of the therapeutic effects.
 16. The external programmer of claim 14, wherein the graphical indication of the one or more clinical effects comprises a bar map for each of the electrode combinations, each bar map having a bar indicating the relative level of the one or more therapeutic effects at the each incremental intensity level.
 17. The external programmer of claim 9, wherein the processing circuitry is configured to determine the influence of the each different electrode combination on the one or more clinical effects by determining electrode combinations that most influence the one or more therapeutic effects, and wherein the graphical indication of the one or more clinical effects comprises at least one target tissue region displayed adjacent the graphical rendering of the electrodes determined to most influence the one or more therapeutic effects.
 18. The external programmer of claim 17, wherein the processing circuitry is further configured to determine the influence of the each different electrode combination on the one or more clinical effects by determining electrode combinations that most influence the side-effect, and wherein the graphical indication of the one or more clinical effects comprises at least one non-target tissue region displayed adjacent the electrode combinations in a graphical electrode representation determined to most influence the side-effect.
 19. The external programmer of claim 17, wherein the processing circuitry is further configured to estimate one of an electric field or a region of tissue activation at a highest incremental intensity level at which the one or more therapeutic effects occurs for the each different electrode combination, wherein the at least one target tissue region is based on the estimated electric field or region of tissue activation.
 20. The external programmer of claim 1, wherein the control circuitry is further configured to program the neurostimulator via the output circuitry based on the extent to which the each different electrode combination influences the one or more clinical effects.
 21. The external programmer of claim 1, further comprising memory configured to store data indicating the determined influence of the each different electrode combination on the one or more clinical effects.
 22. A method of treating a patient using the external programmer of claim 1, comprising: conveying the electrical stimulation energy into tissue of the patient via the different combinations of electrodes implanted within the patient, thereby creating the one or more clinical effects for each of the different electrode combinations; determining the influence of each different electrode combinations on the one or more clinical effects; generating the graphical indication of the one or more clinical effects based on the determined electrode combination influences; displaying the graphical rendering of the electrodes; and displaying the graphical indication of the one or more clinical effects adjacent the graphical electrode representation, such that the user can determine the extent to which each of the different electrode combinations influences the one or more clinical effects.
 23. The method of claim 22, wherein each of the electrode combinations has only one electrode.
 24. The method of claim 22, wherein at least one of the electrode combinations comprises a fractionalized electrode combination.
 25. The method of claim 22, wherein the one or more clinical effects comprises a therapeutic effect.
 26. The method of claim 22, wherein the one or more clinical effects comprises a side-effect.
 27. The method of claim 22, further comprising incrementally increasing an intensity level of the conveyed electrical stimulation energy for each of the different electrode combinations, wherein the influence of the each different electrode combination on the one or more clinical effects is determined for each of the incremental intensity levels.
 28. The method of claim 27, wherein the one or more clinical effects comprises one or more therapeutic effects, and the influence of the each different electrode combination on the one or more therapeutic effects is determined by determining the range of incremental intensity levels at which a metric of the one or more therapeutic effects occurs.
 29. The method of claim 28, wherein the one or more clinical effects further comprises one or more side-effects, and the influence of the each different electrode combination on the one or more side-effects is determined by determining the incremental intensity level at which a metric of the one or more side-effects initially occurs.
 30. The method of claim 29, wherein the influence of the each different electrode combination on the one or more therapeutic effects is further determined by determining the highest intensity level at which the one or more therapeutic effect metrics occur prior to the initial occurrence of the one or more side-effect metrics.
 31. The method of claim 30, wherein the graphical indication of the one or more clinical effects comprises a bar map having a plurality of bars, each of which indicates for the each different electrode combination the highest intensity level at which the one or more therapeutic effect metrics occur prior to the initial occurrence of the one or more side-effect metrics.
 32. The method of claim 31, wherein the therapeutic effect metric is a perception threshold of the one or more therapeutic effects, and the side-effect metric is one of a perception threshold of the one or more side-effects, an uncomfortable threshold of the one or more side-effects, and an intolerable threshold of the one or more side-effects.
 33. The method of claim 28, wherein the therapeutic effect metric is a relative level of the one or more therapeutic effects.
 34. The method of claim 33, wherein the one or more therapeutic effects comprises a plurality of therapeutic effects, and the relative level is a composite score as a function of individual scores of the therapeutic effects.
 35. The method of claim 33, wherein the graphical indication of the one or more clinical effects comprises a bar map for each of the electrode combinations, each bar map having a bar indicating the relative level of the one or more therapeutic effects at the each incremental intensity level.
 36. The method of claim 28, wherein the influence of the each different electrode combination on the one or more clinical effects is determined by determining the electrode combinations that most influence the one or more therapeutic effects, and wherein the graphical indication of the one or more clinical effects comprises at least one target tissue region displayed adjacent the electrode combinations in the graphical electrode representation determined to most influence the one or more therapeutic effects.
 37. The method of claim 36, wherein the influence of the each different electrode combination on the one or more clinical effects is determined by determining the electrode combinations that most influence the side-effect, and wherein the graphical indication of the one or more clinical effects comprises at least one non-target tissue region displayed adjacent the electrode combinations in the graphical electrode representation determined to most influence the side-effect.
 38. The method of claim 36, further comprising estimating one of an electric field or a region of tissue activation at the highest incremental intensity level at which the one or more therapeutic effects occurs for the each different electrode combination, wherein the target tissue region is based on the estimated electric field or region of tissue activation.
 39. The method of claim 22, wherein the electrical stimulation energy is conveyed from a neurostimulator, the method further comprising programming the neurostimulator based on the determined extent to which the each different electrode combination influences the one or more clinical effects.
 40. The method of claim 22, further comprising recording data in computer memory indicating the determined influence of the each different electrode combination on the one or more clinical effects.
 41. The method of claim 22, wherein the tissue is brain tissue. 